U.S. patent number 6,517,176 [Application Number 09/672,309] was granted by the patent office on 2003-02-11 for liquid jetting apparatus.
This patent grant is currently assigned to Seiko Epson Corporation. Invention is credited to Junhua Chaug.
United States Patent |
6,517,176 |
Chaug |
February 11, 2003 |
Liquid jetting apparatus
Abstract
A liquid jetting apparatus of the invention includes a head
having a nozzle, a pressure-changing unit for causing pressure of
liquid in the nozzle to change in such a manner that the liquid is
jetted from the nozzle, and a jetting-mode setting unit for setting
a selected jetting mode from a plurality of jetting modes. A
level-data setting unit sets a selected level data from a plurality
of level data, based on a jetting data. A driving-signal generator
generates a driving signal, based on the selected jetting mode. A
driving-pulse generator generates a driving pulse based on the
selected level data and the driving signal. A main controller
causes the pressure-changing unit to operate, based on the driving
pulse. Driving pulses generated based on a selected jetting mode
and respective selected level data are different from driving
pulses generated based on another selected jetting mode and the
respective selected level data.
Inventors: |
Chaug; Junhua (Nagano-Ken,
JP) |
Assignee: |
Seiko Epson Corporation (Tokyo,
JP)
|
Family
ID: |
17630318 |
Appl.
No.: |
09/672,309 |
Filed: |
September 29, 2000 |
Foreign Application Priority Data
|
|
|
|
|
Sep 30, 1999 [JP] |
|
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11-280811 |
|
Current U.S.
Class: |
347/11;
347/9 |
Current CPC
Class: |
B41J
2/04551 (20130101); B41J 2/04581 (20130101); B41J
2/04588 (20130101); B41J 2/04593 (20130101); B41J
2/04595 (20130101); B41J 2/04596 (20130101) |
Current International
Class: |
B41J
2/045 (20060101); B41J 029/38 () |
Field of
Search: |
;347/10,11 |
References Cited
[Referenced By]
U.S. Patent Documents
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5515085 |
May 1996 |
Hotomi et al. |
5529617 |
June 1996 |
Yamashita et al. |
6086189 |
July 2000 |
Hosono et al. |
6151050 |
November 2000 |
Hosono et al. |
6227649 |
May 2001 |
Hirabayashi et al. |
6293643 |
September 2001 |
Shimada et al. |
6328395 |
December 2001 |
Kitahara et al. |
6356358 |
March 2002 |
Kakutani et al. |
|
Foreign Patent Documents
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0 827 838 |
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Mar 1998 |
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EP |
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0 885 732 |
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Dec 1998 |
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EP |
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0 893 260 |
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Jan 1999 |
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0 913 256 |
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EP |
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1 106 360 |
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Jun 2001 |
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EP |
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63-188055 |
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Aug 1988 |
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JP |
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8-336970 |
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Dec 1996 |
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JP |
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10-81014 |
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Mar 1998 |
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JP |
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10-109433 |
|
Apr 1998 |
|
JP |
|
11-151821 |
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Jun 1999 |
|
JP |
|
11-228888 |
|
Aug 1999 |
|
JP |
|
Primary Examiner: Tran; Huan
Assistant Examiner: Dudding; Alfred E
Attorney, Agent or Firm: Oblon, Spivak, McClelland, Maier
& Neustadt, P.C.
Claims
What is claimed is:
1. A liquid jetting apparatus comprising a head having a nozzle, a
pressure-changing unit for causing a pressure of liquid in the
nozzle to change in such a manner that the liquid is jetted from
the nozzle, a jetting-mode setting unit for setting a selected
jetting mode from a plurality of jetting modes, a level-data
setting unit for setting a selected level data from a plurality of
level data, based on a jetting data, a driving-signal generator for
generating a driving signal, based on the selected jetting mode, a
driving-pulse generator for generating a driving pulse based on the
selected level data and the driving signal, and a main controller
for causing the pressure-changing unit to operate, based on the
driving pulse, wherein driving pulses generated based on a selected
jetting mode and respective selected level data are different from
driving pulses generated based on another selected jetting mode and
the respective selected level data, and wherein: the plurality of
jetting modes include a first jetting mode and a second jetting
mode, the plurality of level data include a small-dot data, a
middle-dot data and a large-dot data, the driving signal generated
based on the first jetting mode is a periodical signal including n
separated small-drop pulse-waves, each of which is for jetting a
small drop of the liquid from the nozzle, n being not less than
three, the driving-pulse generator is adapted to generate, based on
the driving signal generated based on the first jetting mode: a
driving-pulse including only p small-drop pulse-waves when the
selected level data is the small-dot data, p being one or more, a
driving-pulse including only q small-drop pulse-waves when the
selected level data is the middle-dot data, q being more than p,
and a driving-pulse including r small-drop pulse-waves when the
selected level data is the large-dot data, r being more than q and
not more than n, the driving signal generated based on the second
jetting mode is a periodical signal including: a small-dot
pulse-wave for jetting a small-dot drop of the liquid from the
nozzle, a middle-dot pulse-wave for jetting a middle-dot drop of
the liquid from the nozzle, and a large-dot pulse-wave for jetting
two or more drops of the liquid from the nozzle, the two or more
drops corresponding to a large-dot drop, the driving-pulse
generator is adapted to generate, based on the driving signal
generated based on the second jetting mode: a driving-pulse
including only the small-dot pulse-wave when the selected level
data is the small-dot data, driving-pulse including only the
middle-dot pulse-wave when the selected level data is the
middle-dot data, and a driving-pulse including only the large-dot
pulse-wave when the selected level data is the large-dot data, and
jetting by the second jetting mode is superior to jetting by the
first jetting mode in quality.
2. A liquid jetting apparatus comprising a head having a nozzle, a
pressure-changing unit for causing a pressure of liquid in the
nozzle to change in such a manner that the liquid is jetted from
the nozzle, a jetting-mode setting unit for setting a selected
jetting mode from a plurality of jetting modes, a level-data
setting unit for setting a selected level data from a plurality of
level data, based on a jetting data, a driving-signal generator for
generating a driving signal, based on the selected jetting mode, a
driving-pulse generator for generating a driving pulse based on the
selected level data and the driving signal, and a main controller
for causing the pressure-changing unit to operate, based on the
driving pulse, wherein driving pulses generated based on a selected
jetting mode and respective selected level data are different from
driving pulses generated based on another selected jetting mode and
the respective selected level data, and wherein: the plurality of
jetting modes include a first jetting mode and a second jetting
mode, the plurality of level data include a small-dot data, a
middle-dot data and a large-dot data, the driving signal generated
based on the first jetting mode is a periodical signal including
three separated small-dot pulse-waves, each of which is for jetting
a small-dot drop of the liquid from the nozzle, the driving-pulse
generator is adapted to generate, based on the driving signal
generated based on the first jetting mode: a driving-pulse
including only one small-dot pulse-wave when the selected level
data is the small-dot data, a driving-pulse including only two
small-dot pulse-waves when the selected level data is the
middle-dot data, and a driving-pulse including all the three
small-dot pulse-waves when the selected level data is the large-dot
data, the driving signal generated based on the second jetting mode
is a periodical signal including: a small-dot pulse-wave for
jetting a small-dot drop of the liquid from the nozzle, and a
middle-dot pulse-wave for jetting a middle-dot drop of the liquid
from the nozzle, the middle-dot pulse-wave being separated from the
small-dot pulse-wave, the driving-pulse generator is adapted to
generate, based on the driving signal generated based on the second
jetting mode: a driving-pulse including only the small-dot
pulse-wave when the selected level data is the small-dot data, a
driving-pulse including only the middle-dot pulse-wave when the
selected level data is the middle-dot data, and a driving-pulse
including both the small-dot pulse-wave and the middle-dot
pulse-wave when the selected level data is the large-dot data, and
jetting by the second jetting mode is superior to jetting by the
first jetting mode in quality.
3. A liquid jetting apparatus comprising a head having a nozzle, a
pressure-changing unit for causing a pressure of liquid in the
nozzle to change in such a manner that the liquid is jetted from
the nozzle, a jetting-mode setting unit for setting a selected
jetting mode from a plurality of jetting modes, a level-data
setting unit for setting a selected level data from a plurality of
level data, based on a jetting data, a driving-signal generator for
generating a driving signal, based on the selected jetting mode, a
driving-pulse generator for generating a driving pulse based on the
selected level data and the driving signal, and a main controller
for causing the pressure-changing unit to operate, based on the
driving pulse, wherein driving pulses generated based on a selected
jetting mode and respective selected level data are different from
driving pulses generated based on another selected jetting mode and
the respective selected level data, and wherein: the plurality of
jetting modes include a first jetting mode and a second jetting
mode, the plurality of level data include a small-dot data, a
middle-dot data and a large-dot data, the driving signal generated
based on the first jetting mode is a periodical signal including
three separated small-dot pulse-waves, each of which is for jetting
a small-dot drop of the liquid from the nozzle, the driving-pulse
generator is adapted to generate, based on the driving signal
generated based on the first jetting mode: a driving-pulse
including only one small-dot pulse-wave when the selected level
data is the small-dot data, a driving-pulse including only two
small-dot pulse-waves when the selected level data is the
middle-dot data, and a driving-pulse including all the three
small-dot pulse-waves when the selected level data is the large-dot
data, the driving signal generated based on the second jetting mode
is a periodical signal including: a small-dot pulse-wave for
jetting a small-dot drop of the liquid from the nozzle, a
middle-dot pulse-wave for jetting a middle-dot drop of the liquid
from the nozzle, the middle-dot pulse-wave being separated from the
small-dot pulse-wave, and an additional large-dot pulse-wave for
jetting a second drop of the liquid from the nozzle, a combination
of the second drop and the middle-dot drop corresponding to a
large-dot drop, the driving-pulse generator is adapted to generate,
based on the driving signal generated based on the second jetting
mode: a driving-pulse including only the small-dot pulse-wave when
the selected level data is the small-dot data, a driving-pulse
including only the middle-dot pulse-wave when the selected level
data is the middle-dot data, and a driving-pulse including both the
middle-dot pulse-wave and the additional large-dot pulse-wave when
the selected level data is the large-dot data, and jetting by the
second jetting mode is superior to jetting by the first jetting
mode in quality.
4. A liquid jetting apparatus comprising a head having a nozzle, a
pressure-changing unit for causing a pressure of liquid in the
nozzle to change in such a manner that the liquid is jetted from
the nozzle, a jetting-mode setting unit for setting a selected
jetting mode from a plurality of jetting modes, a level-data
setting unit for setting a selected level data from a plurality of
level data, based on a jetting data, a driving-signal generator for
generating a driving signal, based on the selected jetting mode, a
driving-pulse generator for generating a driving pulse based on the
selected level data and the driving signal, and a main controller
for causing the pressure-changing unit to operate, based on the
driving pulse, wherein driving pulses generated based on a selected
jetting mode and respective selected level data are different from
driving pulses generated based on another selected jetting mode and
the respective selected level data, and wherein: the plurality of
jetting modes include a third jetting mode, the plurality of level
data include a small-dot data, a middle-dot data and a large-dot
data, the driving signal generated based on the third jetting mode
is a periodical signal including: a small-dot pulse-wave for
jetting a small-dot drop of the liquid from the nozzle, a
middle-dot pulse-wave for jetting a middle-dot drop of the liquid
from the nozzle, and a large-dot pulse-wave for jetting a large-dot
drop of the liquid from the nozzle, and the driving-pulse generator
is adapted to generate, based on the driving signal generated based
on the third jetting mode: a driving-pulse including only the
small-dot pulse-wave when the selected level data is the small-dot
data, a driving-pulse including only the middle-dot pulse-wave when
the selected level data is the middle-dot data, and a driving-pulse
including only the large-dot pulse-wave when the selected level
data is the large-dot data.
5. A liquid jetting apparatus comprising a head having a nozzle, a
pressure-changing unit for causing a pressure of liquid in the
nozzle to change in such a manner that the liquid is jetted from
the nozzle, a jetting-mode setting unit for setting a selected
jetting mode from a plurality of jetting modes, a level-data
setting unit for setting a selected level data from a plurality of
level data, based on a jetting data, a driving-signal generator for
generating a driving signal, based on the selected jetting mode, a
driving-pulse generator for generating a driving pulse based on the
selected level data and the driving signal, and a main controller
for causing the pressure-changing unit to operate, based on the
driving pulse, wherein driving pulses generated based on a selected
jetting mode and respective selected level data are different from
driving pulses generated based on another selected jetting mode and
the respective selected level data, and wherein: the plurality of
jetting modes include a second jetting mode and a third jetting
mode, the plurality of level data include a small-dot data, a
middle-dot data and a large-dot data, the driving signal generated
based on the second jetting mode is a periodical signal including:
a small-dot pulse-wave for jetting a small-dot drop of the liquid
from the nozzle, a middle-dot pulse-wave for jetting a middle-dot
drop of the liquid from the nozzle, and a large-dot pulse-wave for
jetting two or more drops of the liquid from the nozzle, the two or
more drops corresponding to a large-dot drop, the driving-pulse
generator is adapted to generate, based on the driving signal
generated based on the second jetting mode: a driving-pulse
including only the small-dot pulse-wave when the selected level
data is the small-dot data, a driving-pulse including only the
middle-dot pulse-wave when the selected level data is the
middle-dot data, and a driving-pulse including only the large-dot
pulse-wave when the selected level data is the large-dot data, the
driving signal generated based on the third jetting mode is a
periodical signal including: a small-dot pulse-wave for jetting a
small-dot drop of the liquid from the nozzle, a middle-dot
pulse-wave for jetting a middle-dot drop of the liquid from the
nozzle, and a large-dot pulse-wave for jetting a large-dot drop of
the liquid from the nozzle, the driving-pulse generator is adapted
to generate, based on the driving signal generated based on the
third jetting mode: a driving-pulse including only the small-dot
pulse-wave when the selected level data is the small-dot data, a
driving-pulse including only the middle-dot pulse-wave when the
selected level data is the middle-dot data, and a driving-pulse
including only the large-dot pulse-wave when the selected level
data is the large-dot data, and jetting by the third jetting mode
is superior to jetting by the second jetting mode in quality.
6. A liquid jetting apparatus comprising a head having a nozzle, a
pressure-changing unit for causing a pressure of liquid in the
nozzle to change in such a manner that the liquid is jetted from
the nozzle, a jetting-mode setting unit for setting a selected
jetting mode from a plurality of jetting modes, a level-data
setting unit for setting a selected level data from a plurality of
level data, based on a jetting data, a driving-signal generator for
generating a driving signal, based on the selected jetting mode, a
driving-pulse generator for generating a driving pulse based on the
selected level data and the driving signal, and a main controller
for causing the pressure-changing unit to operate, based on the
driving pulse, wherein driving pulses generated based on a selected
jetting mode and respective selected level data are different from
driving pulses generated based on another selected jetting mode and
the respective selected level data, and wherein: the plurality of
jetting modes include a second jetting mode and a third jetting
mode, the plurality of level data include a small-dot data, a
middle-dot data and a large-dot data, the driving signal generated
based on the second jetting mode is a periodical signal including:
a small-dot pulse-wave for jetting a small-dot drop of the liquid
from the nozzle, and a middle-dot pulse-wave for jetting a
middle-dot drop of the liquid from the nozzle, the middle-dot
pulse-wave being separated from the small-dot pulse-wave, the
driving-pulse generator is adapted to generate, based on the
driving signal generated based on the second jetting mode: a
driving-pulse including only the small-dot pulse-wave when the
selected level data is the small-dot data, a driving-pulse
including only the middle-dot pulse-wave when the selected level
data is the middle-dot data, and a driving-pulse including both the
small-dot pulse-wave and the middle-dot pulse-wave when the
selected level data is the large-dot data, the driving signal
generated based on the third jetting mode is a periodical signal
including: a small-dot pulse-wave for jetting a small-dot drop of
the liquid from the nozzle, a middle-dot pulse-wave for jetting a
middle-dot drop of the liquid from the nozzle, and a large-dot
pulse-wave for jetting a large-dot drop of the liquid from the
nozzle, the driving-pulse generator is adapted to generate, based
on the driving signal generated based on the third jetting mode: a
driving-pulse including only the small-dot pulse-wave when the
selected level data is the small-dot data, a driving-pulse
including only the middle-dot pulse-wave when the selected level
data is the middle-dot data, and a driving-pulse including only the
large-dot pulse-wave when the selected level data is the large-dot
data, and jetting by the third jetting mode is superior to jetting
by the second jetting mode in quality.
7. A liquid jetting apparatus according to claim 6, wherein: a
volume of the liquid jetted from the nozzle based on the small-dot
pulse-wave of the second jetting mode is 3 to 9 pl, a volume of the
liquid jetted from the nozzle based on the middle-dot pulse-wave of
the second jetting mode is 9 to 15 pl, a volume of the liquid
jetted from the nozzle based on the small-dot pulse-wave and the
middle-dot pulse-wave of the second jetting mode is 17 to 30 pl, a
volume of the liquid jetted from the nozzle based on the small-dot
pulse-wave of the third jetting mode is 0.5 to 4 pl, a volume of
the liquid jetted from the nozzle based on the middle-dot
pulse-wave of the third jetting mode is 5 to 10 pl, and a volume of
the liquid jetted from the nozzle based on the large-dot pulse-wave
of the third jetting mode is 10 to 20 pl.
8. A liquid jetting apparatus comprising a head having a nozzle, a
pressure-changing unit for causing a pressure of liquid in the
nozzle to change in such a manner that the liquid is jetted from
the nozzle, a jetting-mode setting unit for setting a selected
jetting mode from a plurality of jetting modes, a level-data
setting unit for setting a selected level data from a plurality of
level data, based on a jetting data, a driving-signal generator for
generating a driving signal, based on the selected jetting mode, a
driving-pulse generator for generating a driving pulse based on the
selected level data and the driving signal, and a main controller
for causing the pressure-changing unit to operate, based on the
driving pulse, wherein driving pulses generated based on a selected
jetting mode and respective selected level data are different from
driving pulses generated based on another selected jetting mode and
the respective selected level data, and wherein: the plurality of
jetting modes include a second jetting mode and a third jetting
mode, the plurality of level data include a small-dot data, a
middle-dot data and a large-dot data, the driving signal generated
based on the second jetting mode is a periodical signal including:
a small-dot pulse-wave for jetting a small-dot drop of the liquid
from the nozzle, a middle-dot pulse-wave for jetting a middle-dot
drop of the liquid from the nozzle, the middle-dot pulse-wave being
separated from the small-dot pulse-wave, and an additional
large-dot pulse-wave for jetting a second drop of the liquid from
the nozzle, a combination of the second drop and the middle-dot
drop corresponding to a large-dot drop, the driving-pulse generator
is adapted to generate, based on the driving signal generated based
on the second jetting mode: a driving-pulse including only the
small-dot pulse-wave when the selected level data is the small-dot
data, a driving-pulse including only the middle-dot pulse-wave when
the selected level data is the middle-dot data, and a driving-pulse
including both the middle-dot pulse-wave and the additional
large-dot pulse-wave when the selected level data is the large-dot
data, the driving signal generated based on the third jetting mode
is a periodical signal including: a small-dot pulse-wave for
jetting a small-dot drop of the liquid from the nozzle, a
middle-dot pulse-wave for jetting a middle-dot drop of the liquid
from the nozzle, and a large-dot pulse-wave for jetting a large-dot
drop of the liquid from the nozzle, the driving-pulse generator is
adapted to generate, based on the driving signal generated based on
the third jetting mode: a driving-pulse including only the
small-dot pulse-wave when the selected level data is the small-dot
data, a driving-pulse including only the middle-dot pulse-wave when
the selected level data is the middle-dot data, and a driving-pulse
including only the large-dot pulse-wave when the selected level
data is the large-dot data, and jetting by the third jetting mode
is superior to jetting by the second jetting mode in quality.
9. A liquid jetting apparatus according to claim 8, wherein: a
volume of the liquid jetted from the nozzle based on the small-dot
pulse-wave of the second jetting mode is 3 to 9 pl, a volume of the
liquid jetted from the nozzle based on the middle-dot pulse-wave of
the second jetting mode is 9 to 15 pl, a volume of the liquid
jetted from the nozzle based on the middle-dot pulse-wave and the
additional large-dot pulse-wave of the second jetting mode is 17 to
30 pl, a volume of the liquid jetted from the nozzle based on the
small-dot pulse-wave of the third jetting mode is 0.5 to 4 pl, a
volume of the liquid jetted from the nozzle based on the middle-dot
pulse-wave of the third jetting mode is 5 to 10 pl, and a volume of
the liquid jetted from the nozzle based on the large-dot pulse-wave
of the third jetting mode is 10 to 20 pl.
10. A controlling unit for controlling a liquid jetting apparatus
including a head having a nozzle, and a pressure-changing unit for
causing pressure of liquid in the nozzle to change in such a manner
that the liquid is jetted from the nozzle, comprising a
jetting-mode setting unit for setting a selected jetting mode from
a plurality of jetting modes, a level-data setting unit for setting
a selected level data from a plurality of level data, based on a
jetting data, a driving-signal generator for generating a driving
signal, based on the selected jetting mode, a driving-pulse
generator for generating a driving pulse based on the selected
level data and the driving signal, and a main controller for
causing the pressure-changing unit to operate, based on the driving
pulse, wherein driving pulses generated based on a selected jetting
mode and respective selected level data are different from driving
pulses generated based on another selected jetting mode and the
respective selected level data, and wherein: the plurality of
jetting modes include a first jetting mode and a second jetting
mode, the plurality of level data include a small-dot data, a
middle-dot data and a large-dot data, the driving signal generated
based on the first jetting mode is a periodical signal including n
separated small-drop pulse-waves, each of which is for jetting a
small drop of the liquid from the nozzle, n being not less than
three, the driving-pulse generator is adapted to generate, based on
the driving signal generated based on the first jetting mode: a
driving-pulse including only p small-drop pulse-waves when the
selected level data is the small-dot data, p being one or more, a
driving-pulse including only q small-drop pulse-waves when the
selected level data is the middle-dot data, q being more than p,
and a driving-pulse including r small-drop pulse-waves when the
selected level data is the large-dot data, r being more than q and
not more than n, the driving signal generated based on the second
jetting mode is a periodical signal including: a small-dot
pulse-wave for jetting a small-dot drop of the liquid from the
nozzle, a middle-dot pulse-wave for jetting a middle-dot drop of
the liquid from the nozzle, and a large-dot pulse-wave for jetting
two or more drops of the liquid from the nozzle, the two or more
drops corresponding to a large-dot drop, the driving-pulse
generator is adapted to generate, based on the driving signal
generated based on the second jetting mode: a driving-pulse
including only the small-dot pulse-wave when the selected level
data is the small-dot data, a driving-pulse including only the
middle-dot pulse-wave when the selected level data is the
middle-dot data, and a driving-pulse including only the large-dot
pulse-wave when the selected level data is the large-dot data, and
jetting by the second jetting mode is superior to jetting by the
first jetting mode in quality.
11. A controlling unit for controlling a liquid jetting apparatus
including a head having a nozzle, and a pressure-changing unit for
causing pressure of liquid in the nozzle to change in such a manner
that the liquid is jetted from the nozzle, comprising a
jetting-mode setting unit for setting a selected jetting mode from
a plurality of jetting modes, a level-data setting unit for setting
a selected level data from a plurality of level data, based on a
jetting data, a driving-signal generator for generating a driving
signal, based on the selected jetting mode, a driving-pulse
generator for generating a driving pulse based on the selected
level data and the driving signal, and a main controller for
causing the pressure-changing unit to operate, based on the driving
pulse, wherein driving pulses generated based on a selected jetting
mode and respective selected level data are different from driving
pulses generated based on another selected jetting mode and the
respective selected level data, and wherein: the plurality of
jetting modes include a first jetting mode and a second jetting
mode, the plurality of level data include a small-dot data, a
middle-dot data and a large-dot data, the driving signal generated
based on the first jetting mode is a periodical signal including
three separated small-dot pulse-waves, each of which is for jetting
a small-dot drop of the liquid from the nozzle, the driving-pulse
generator is adapted to generate, based on the driving signal
generated based on the first jetting mode: a driving-pulse
including only one small-dot pulse-wave when the selected level
data is the small-dot data, a driving-pulse including only two
small-dot pulse-waves when the selected level data is the
middle-dot data, and a driving-pulse including all the three
small-dot pulse-waves when the selected level data is the large-dot
data, the driving signal generated based on the second jetting mode
is a periodical signal including: a small-dot pulse-wave for
jetting a small-dot drop of the liquid from the nozzle, and a
middle-dot pulse-wave for jetting a middle-dot drop of the liquid
from the nozzle, the middle-dot pulse-wave being separated from the
small-dot pulse-wave, the driving-pulse generator is adapted to
generate, based on the driving signal generated based on the second
jetting mode: a driving-pulse including only the small-dot
pulse-wave when the selected level data is the small-dot data, a
driving-pulse including only the middle-dot pulse-wave when the
selected level data is the middle-dot data, and a driving-pulse
including both the small-dot pulse-wave and the middle-dot
pulse-wave when the selected level data is the large-dot data, and
jetting by the second jetting mode is superior to jetting by the
first jetting mode in quality.
12. A controlling unit for controlling a liquid jetting apparatus
including a head having a nozzle, and a pressure-changing unit for
causing pressure of liquid in the nozzle to change in such a manner
that the liquid is jetted from the nozzle, comprising a
jetting-mode setting unit for setting a selected jetting mode from
a plurality of jetting modes, a level-data setting unit for setting
a selected level data from a plurality of level data, based on a
jetting data, a driving-signal generator for generating a driving
signal, based on the selected jetting mode, a driving-pulse
generator for generating a driving pulse based on the selected
level data and the driving signal, and a main controller for
causing the pressure-changing unit to operate, based on the driving
pulse, wherein driving pulses generated based on a selected jetting
mode and respective selected level data are different from driving
pulses generated based on another selected jetting mode and the
respective selected level data, and wherein: the plurality of
jetting modes include a first jetting mode and a second jetting
mode, the plurality of level data include a small-dot data, a
middle-dot data and a large-dot data, the driving signal generated
based on the first jetting mode is a periodical signal including
three separated small-dot pulse-waves, each of which is for jetting
a small-dot drop of the liquid from the nozzle, the driving-pulse
generator is adapted to generate, based on the driving signal
generated based on the first jetting mode: a driving-pulse
including only one small-dot pulse-wave when the selected level
data is the small-dot data, a driving-pulse including only two
small-dot pulse-waves when the selected level data is the
middle-dot data, and a driving-pulse including all the three
small-dot pulse-waves when the selected level data is the large-dot
data, the driving signal generated based on the second jetting mode
is a periodical signal including: a small-dot pulse-wave for
jetting a small-dot drop of the liquid from the nozzle, a
middle-dot pulse-wave for jetting a middle-dot drop of the liquid
from the nozzle, the middle-dot pulse-wave being separated from the
small-dot pulse-wave, and an additional large-dot pulse-wave for
jetting a second drop of the liquid from the nozzle, a combination
of the second drop and the middle-dot drop corresponding to a
large-dot drop, the driving-pulse generator is adapted to generate,
based on the driving signal generated based on the second jetting
mode: a driving-pulse including only the small-dot pulse-wave when
the selected level data is the small-dot data, a driving-pulse
including only the middle-dot pulse-wave when the selected level
data is the middle-dot data, and a driving-pulse including both the
middle-dot pulse-wave and the additional large-dot pulse-wave when
the selected level data is the large-dot data, and jetting by the
second jetting mode is superior to jetting by the first jetting
mode in quality.
13. A controlling unit for controlling a liquid jetting apparatus
including a head having a nozzle, and a pressure-changing unit for
causing pressure of liquid in the nozzle to change in such a manner
that the liquid is jetted from the nozzle, comprising a
jetting-mode setting unit for setting a selected jetting mode from
a plurality of jetting modes, a level-data setting unit for setting
a selected level data from a plurality of level data, based on a
jetting data, a driving-signal generator for generating a driving
signal, based on the selected jetting mode, a driving-pulse
generator for generating a driving pulse based on the selected
level data and the driving signal, and a main controller for
causing the pressure-changing unit to operate, based on the driving
pulse, wherein driving pulses generated based on a selected jetting
mode and respective selected level data are different from driving
pulses generated based on another selected jetting mode and the
respective selected level data, and wherein: the plurality of
jetting modes include a third jetting mode, the plurality of level
data include a small-dot data, a middle-dot data and a large-dot
data, the driving signal generated based on the third jetting mode
is a periodical signal including: a small-dot pulse-wave for
jetting a small-dot drop of the liquid from the nozzle, a
middle-dot pulse-wave for jetting a middle-dot drop of the liquid
from the nozzle, and a large-dot pulse-wave for jetting a large-dot
drop of the liquid from the nozzle, and the driving-pulse generator
is adapted to generate, based on the driving signal generated based
on the third jetting mode: a driving-pulse including only the
small-dot pulse-wave when the selected level data is the small-dot
data, a driving-pulse including only the middle-dot pulse-wave when
the selected level data is the middle-dot data, and a driving-pulse
including only the large-dot pulse-wave when the selected level
data is the large-dot data.
14. A controlling unit for controlling a liquid jetting apparatus
including a head having a nozzle, and a pressure-changing unit for
causing pressure of liquid in the nozzle to change in such a manner
that the liquid is jetted from the nozzle, comprising a
jetting-mode setting unit for setting a selected jetting mode from
a plurality of jetting modes, a level-data setting unit for setting
a selected level data from a plurality of level data, based on a
jetting data, a driving-signal generator for generating a driving
signal, based on the selected jetting mode, a driving-pulse
generator for generating a driving pulse based on the selected
level data and the driving signal, and a main controller for
causing the pressure-changing unit to operate, based on the driving
pulse, wherein driving pulses generated based on a selected jetting
mode and respective selected level data are different from driving
pulses generated based on another selected jetting mode and the
respective selected level data, and wherein: the plurality of
jetting modes include a second jetting mode and a third jetting
mode, the plurality of level data include a small-dot data, a
middle-dot data and a large-dot data, the driving signal generated
based on the second jetting mode is a periodical signal including:
a small-dot pulse-wave for jetting a small-dot drop of the liquid
from the nozzle, a middle-dot pulse-wave for jetting a middle-dot
drop of the liquid from the nozzle, and a large-dot pulse-wave for
jetting two or more drops of the liquid from the nozzle, the two or
more drops corresponding to a large-dot drop, the driving-pulse
generator is adapted to generate, based on the driving signal
generated based on the second jetting mode: a driving-pulse
including only the small-dot pulse-wave when the selected level
data is the small-dot data, a driving-pulse including only the
middle-dot pulse-wave when the selected level data is the
middle-dot data, and a driving-pulse including only the large-dot
pulse-wave when the selected level data is the large-dot data, the
driving signal generated based on the third jetting mode is a
periodical signal including: a small-dot pulse-wave for jetting a
small-dot drop of the liquid from the nozzle, a middle-dot
pulse-wave for jetting a middle-dot drop of the liquid from the
nozzle, and a large-dot pulse-wave for jetting a large-dot drop of
the liquid from the nozzle, the driving-pulse generator is adapted
to generate, based on the driving signal generated based on the
third jetting mode: a driving-pulse including only the small-dot
pulse-wave when the selected level data is the small-dot data, a
driving-pulse including only the middle-dot pulse-wave when the
selected level data is the middle-dot data, and a driving-pulse
including only the large-dot pulse-wave when the selected level
data is the large-dot data, and jetting by the third jetting mode
is superior to jetting by the second jetting mode in quality.
15. A controlling unit for controlling a liquid jetting apparatus
including a head having a nozzle, and a pressure-changing unit for
causing pressure of liquid in the nozzle to change in such a manner
that the liquid is jetted from the nozzle, comprising a
jetting-mode setting unit for setting a selected jetting mode from
a plurality of jetting modes, a level-data setting unit for setting
a selected level data from a plurality of level data, based on a
jetting data, a driving-signal generator for generating a driving
signal, based on the selected jetting mode, a driving-pulse
generator for generating a driving pulse based on the selected
level data and the driving signal, and a main controller for
causing the pressure-changing unit to operate, based on the driving
pulse, wherein driving pulses generated based on a selected jetting
mode and respective selected level data are different from driving
pulses generated based on another selected jetting mode and the
respective selected level data, and wherein: the plurality of
jetting modes include a second jetting mode and a third jetting
mode, the plurality of level data include a small-dot data, a
middle-dot data and a large-dot data, the driving signal generated
based on the second jetting mode is a periodical signal including:
a small-dot pulse-wave for jetting a small-dot drop of the liquid
from the nozzle, and a middle-dot pulse-wave for jetting a
middle-dot drop of the liquid from the nozzle, the middle-dot
pulse-wave being separated from the small-dot pulse-wave, the
driving-pulse generator is adapted to generate, based on the
driving signal generated based on the second jetting mode: a
driving-pulse including only the small-dot pulse-wave when the
selected level data is the small-dot data, a driving-pulse
including only the middle-dot pulse-wave when the selected level
data is the middle-dot data, and a driving-pulse including both the
small-dot pulse-wave and the middle-dot pulse-wave when the
selected level data is the large-dot data, the driving signal
generated based on the third jetting mode is a periodical signal
including: a small-dot pulse-wave for jetting a small-dot drop of
the liquid from the nozzle, a middle-dot pulse-wave for jetting a
middle-dot drop of the liquid from the nozzle, and a large-dot
pulse-wave for jetting a large-dot drop of the liquid from the
nozzle, the driving-pulse generator is adapted to generate, based
on the driving signal generated based on the third jetting mode: a
driving-pulse including only the small-dot pulse-wave when the
selected level data is the small-dot data, a driving-pulse
including only the middle-dot pulse-wave when the selected level
data is the middle-dot data, and a driving-pulse including only the
large-dot pulse-wave when the selected level data is the large-dot
data, and jetting by the third jetting mode is superior to jetting
by the second jetting mode in quality.
16. A controlling unit according to claim 15, wherein: a volume of
the liquid jetted from the nozzle based on the small-dot pulse-wave
of the second jetting mode is 3 to 9 pl, a volume of the liquid
jetted from the nozzle based on the middle-dot pulse-wave of the
second jetting mode is 9 to 15 pl, a volume of the liquid jetted
from the nozzle based on the small-dot pulse-wave and the
middle-dot pulse-wave of the second jetting mode is 17 to 30 pl, a
volume of the liquid jetted from the nozzle based on the small-dot
pulse-wave of the third jetting mode is 0.5 to 4 pl, a volume of
the liquid jetted from the nozzle based on the middle-dot
pulse-wave of the third jetting mode is 5 to 10 pl, and a volume of
the liquid jetted from the nozzle based on the large-dot pulse-wave
of the third jetting mode is 10 to 20 pl.
17. A controlling unit for controlling a liquid jetting apparatus
including a head having a nozzle, and a pressure-changing unit for
causing pressure of liquid in the nozzle to change in such a manner
that the liquid is jetted from the nozzle, comprising a
jetting-mode setting unit for setting a selected jetting mode from
a plurality of jetting modes, a level-data setting unit for setting
a selected level data from a plurality of level data, based on a
jetting data, a driving-signal generator for generating a driving
signal, based on the selected jetting mode, a driving-pulse
generator for generating a driving pulse based on the selected
level data and the driving signal, and a main controller for
causing the pressure-changing unit to operate, based on the driving
pulse, wherein driving pulses generated based on a selected jetting
mode and respective selected level data are different from driving
pulses generated based on another selected jetting mode and the
respective selected level data, and wherein: the plurality of
jetting modes include a second jetting mode and a third jetting
mode, the plurality of level data include a small-dot data, a
middle-dot data and a large-dot data, the driving signal generated
based on the second jetting mode is a periodical signal including:
a small-dot pulse-wave for jetting a small-dot drop of the liquid
from the nozzle, a middle-dot pulse-wave for jetting a middle-dot
drop of the liquid from the nozzle, the middle-dot pulse-wave being
separated from the small-dot pulse-wave, and an additional
large-dot pulse-wave for jetting a second drop of the liquid from
the nozzle, a combination of the second drop and the middle-dot
drop corresponding to a large-dot drop, the driving-pulse generator
is adapted to generate, based on the driving signal generated based
on the second jetting mode: a driving-pulse including only the
small-dot pulse-wave when the selected level data is the small-dot
data, a driving-pulse including only the middle-dot pulse-wave when
the selected level data is the middle-dot data, and a driving-pulse
including both the middle-dot pulse-wave and the additional
large-dot pulse-wave when the selected level data is the large-dot
data, the driving signal generated based on the third jetting mode
is a periodical signal including: a small-dot pulse-wave for
jetting a small-dot drop of the liquid from the nozzle, a
middle-dot pulse-wave for jetting a middle-dot drop of the liquid
from the nozzle, and a large-dot pulse-wave for jetting a large-dot
drop of the liquid from the nozzle, the driving-pulse generator is
adapted to generate, based on the driving signal generated based on
the third jetting mode: a driving-pulse including only the
small-dot pulse-wave when the selected level data is the small-dot
data, a driving-pulse including only the middle-dot pulse-wave when
the selected level data is the middle-dot data, and a driving-pulse
including only the large-dot pulse-wave when the selected level
data is the large-dot data, and jetting by the third jetting mode
is superior to jetting by the second jetting mode in quality.
18. A controlling unit according to claim 17, wherein: a volume of
the liquid jetted from the nozzle based on the small-dot pulse-wave
of the second jetting mode is 3 to 9 pl, a volume of the liquid
jetted from the nozzle based on the middle-dot pulse-wave of the
second jetting mode is 9 to 15 pl, a volume of the liquid jetted
from the nozzle based on the middle-dot pulse-wave and the
additional large-dot pulse-wave of the second jetting mode is 17 to
30 pl, a volume of the liquid jetted from the nozzle based on the
small-dot pulse-wave of the third jetting mode is 0.5 to 4 pl, a
volume of the liquid jetted from the nozzle based on the middle-dot
pulse-wave of the third jetting mode is 5 to 10 pl, and a volume of
the liquid jetted from the nozzle based on the large-dot pulse-wave
of the third jetting mode is 10 to 20 pl.
Description
FIELD OF THE INVENTION
This invention relates to a liquid jetting apparatus having a head
capable of jetting a drop of liquid from a nozzle. In particular,
this invention is related to a liquid jetting apparatus having a
head of jetting a plurality of drops of liquid from a nozzle
wherein respective volumes of the plurality of drops of liquid may
be different.
BACKGROUND OF THE INVENTION
In a ink-jetting recording apparatus such as an ink-jetting printer
or an ink-jetting plotter (a kind of liquid jetting apparatus), a
recording head (head) can move in a main scanning direction, and a
recording paper (a kind of recording medium) can move in a
sub-scanning direction perpendicular to the main scanning
direction. While the recording head moves in the main scanning
direction, a drop of ink can be jetted from a nozzle of the
recording head onto the recording paper. Thus, an image including a
character or the like can be recorded on the recording paper. For
example, the drop of ink can be jetted by causing a pressure
chamber communicating with the nozzle to expand and/or
contract.
The pressure chamber may be caused to expand and/or contract, for
example by utilizing deformation of a piezoelectric vibrating
member. In such a recording head, the piezoelectric vibrating
member can be deformed based on a supplied driving-pulse in order
to change a volume of the pressure chamber. When the volume of the
pressure chamber is changed, a pressure of the ink in the pressure
chamber may be changed. Then, the drop of ink is jetted from the
nozzle.
In such a recording apparatus, a driving signal consisting of a
series of a plurality of driving-pulses is generated. On the other
hand, printing data including level data (gradation data) can be
transmitted to the recording head. Then, based on the transmitted
printing data, only necessary one or more driving-pulses are
selected from the driving signal and supplied to the piezoelectric
vibrating member. Thus, a volume of the ink jetted from the nozzle
may be changed based on the level data.
In detail, for example, a ink-jetting printer may be used with four
level data including: a level data 00 for no dot, a level data 01
for a small dot, a level data 10 for a middle dot and a level data
11 for a large dot. In the case, respective volumes of the ink
corresponding to the respective level data may be jetted.
However, recently, it is requested to satisfy user's various
demands with only one ink-jetting recording apparatus. That is, it
is requested that one ink-jetting recording apparatus can achieve a
plurality of detailed demands, for example recording with high
quality, recording at a high speed with not low quality or the
like.
Some conventional ink-jetting recording apparatuses can achieve to
improve quality of printed images by changing volumes of jetted ink
based on a plurality of level data. However, in the conventional
ink-jetting recording apparatuses, the number of the plurality of
level data is too small to satisfy various detailed demands.
The number of bits of level data may be uniformly increased in
order to set the volumes of jetted ink in detail. However, when
printing data include the increased number of bits of level data,
it needs a longer time to transmit the printing data to the
recording head, which results in a low recording speed.
A clock for transmitting the printing data may be one for a higher
speed in order to shorten the time for transmitting the data.
However, the clock for the higher speed needs to use devices
operable with a higher frequency, which results in larger consumed
power and/or a more cost.
SUMMARY OF THE INVENTION
The object of this invention is to solve the above problems, that
is, to provide a liquid jetting apparatus such as an ink-jet
recording apparatus that can satisfy user's various demands by
effectively using a plurality of level data, even when the number
of the plurality of level data is small.
In order to achieve the object, a liquid jetting apparatus
includes: a head having a nozzle; a pressure-changing unit for
causing pressure of liquid in the nozzle to change in such a manner
that the liquid is jetted from the nozzle; a jetting-mode setting
unit for setting a selected jetting mode from a plurality of
jetting modes; a level-data setting unit for setting a selected
level data from a plurality of level data, based on a jetting data;
a driving-signal generator for generating a driving signal, based
on the selected jetting mode; a driving-pulse generator for
generating a driving pulse based on the selected level data and the
driving signal; and a main controller for causing the
pressure-changing unit to operate, based on the driving pulse;
wherein driving pulses generated based on a selected jetting mode
and respective selected level data are different from driving
pulses generated based on another selected jetting mode and the
respective selected level data.
According to the feature, the driving signal is generated based on
the selected jetting mode, and the driving pulse is generated based
on the driving signal and the selected level data based on the
jetting data. Thus, a manner of jetting the liquid by the driving
pulse may be controlled by two factors of the jetting mode and the
level data, which may enable to satisfy the user's various
demands.
Preferably, volumes of the liquid jetted from the nozzle based on
respective driving pulses are different according to respective
jetting modes with respect to a same level data and different
according to respective level data with respect to a same jetting
mode.
According to the feature, since the volumes of the liquid jetted
from the nozzle are different, a jetting speed and/or jetting
quality may be controlled more effectively.
In detail, for example, the driving signal may be a periodical
signal including a plurality of pulse-waves; and the driving pulse
generator is adapted to generate a rectangular-pulse row
corresponding to a period of the driving signal based on the
selected level data, and generate an AND signal of the
rectangular-pulse row and the driving signal as the driving pulse.
In the case, quick signal processing can be achieved.
Preferably, the plurality of jetting modes may include a first
jetting mode, the plurality of level data include a small-dot data,
a middle-dot data and a large-dot data, the driving signal
generated based on the first jetting mode is a periodical signal
including n separated small-drop pulse-waves, each of which is for
jetting a small drop of the liquid from the nozzle, n being not
less than three, and the driving-pulse generator is adapted to
generate, based on the driving signal generated based on the first
jetting mode: a driving-pulse including only p small-drop
pulse-waves when the selected level data is the small-dot data, p
being one or more, a driving-pulse including only q small-drop
pulse-waves when the selected level data is the middle-dot data, q
being more than p, and a driving-pulse including r small-drop
pulse-waves when the selected level data is the large-dot data, r
being more than q and not more than n.
Alternatively, the plurality of jetting modes may include a first
jetting mode, the plurality of level data include a small-dot data,
a middle-dot data and a large-dot data, the driving signal
generated based on the first jetting mode is a periodical signal
including three separated small-dot pulse-waves, each of which is
for jetting a small-dot drop of the liquid from the nozzle, and the
driving-pulse generator is adapted to generate, based on the
driving signal generated based on the first jetting mode: a
driving-pulse including only one small-dot pulse-wave when the
selected level data is the small-dot data, a driving-pulse
including only two small-dot pulse-waves when the selected level
data is the middle-dot data, and a driving-pulse including all the
three small-dot pulse-waves when the selected level data is the
large-dot data.
These first jetting modes are suitable for jetting at a high
speed.
Preferably, the plurality of jetting modes may include a second
jetting mode, the plurality of level data include a small-dot data,
a middle-dot data and a large-dot data, the driving signal
generated based on the second jetting mode is a periodical signal
including: a small-dot pulse-wave for jetting a small-dot drop of
the liquid from the nozzle, a middle-dot pulse-wave for jetting a
middle-dot drop of the liquid from the nozzle, and a large-dot
pulse-wave for jetting two or more drops of the liquid from the
nozzle, the two or more drops corresponding to a large-dot drop,
and the driving-pulse generator is adapted to generate, based on
the driving signal generated based on the second jetting mode: a
driving-pulse including only the small-dot pulse-wave when the
selected level data is the small-dot data, a driving-pulse
including only the middle-dot pulse-wave when the selected level
data is the middle-dot data, and a driving-pulse including only the
large-dot pulse-wave when the selected level data is the large-dot
data.
Alternatively, the plurality of jetting modes may include a second
jetting mode, the plurality of level data include a small-dot data,
a middle-dot data and a large-dot data, the driving signal
generated based on the second jetting mode is a periodical signal
including: a small-dot pulse-wave for jetting a small-dot drop of
the liquid from the nozzle, and a middle-dot pulse-wave for jetting
a middle-dot drop of the liquid from the nozzle, the middle-dot
pulse-wave being separated from the small-dot pulse-wave, and the
driving-pulse generator is adapted to generate, based on the
driving signal generated based on the second jetting mode: a
driving-pulse including only the small-dot pulse-wave when the
selected level data is the small-dot data, a driving-pulse
including only the middle-dot pulse-wave when the selected level
data is the middle-dot data, and a driving-pulse including both the
small-dot pulse-wave and the middle-dot pulse-wave when the
selected level data is the large-dot data.
Alternatively, the plurality of jetting modes may include a second
jetting mode, the plurality of level data include a small-dot data,
a middle-dot data and a large-dot data, the driving signal
generated based on the second jetting mode is a periodical signal
including: a small-dot pulse-wave for jetting a small-dot drop of
the liquid from the nozzle, a middle-dot pulse-wave for jetting a
middle-dot drop of the liquid from the nozzle, the middle-dot
pulse-wave being separated from the small-dot pulse-wave, and an
additional large-dot pulse-wave for jetting a second drop of the
liquid from the nozzle, a combination of the second drop and the
middle-dot drop corresponding to a large-dot drop, and the
driving-pulse generator is adapted to generate, based on the
driving signal generated based on the second jetting mode: a
driving-pulse including only the small-dot pulse-wave when the
selected level data is the small-dot data, a driving-pulse
including only the middle-dot pulse-wave when the selected level
data is the middle-dot data, and a driving-pulse including both the
middle-dot pulse-wave and the additional large-dot pulse-wave when
the selected level data is the large-dot data.
These second jetting modes are suitable for jetting at a middle
speed with high quality.
Preferably, the plurality of jetting modes may include a third
jetting mode, the plurality of level data include a small-dot data,
a middle-dot data and a large-dot data, the driving signal
generated- based on the third jetting mode is a periodical signal
including: a small-dot pulse-wave for jetting a small-dot drop of
the liquid from the nozzle, a middle-dot pulse-wave for jetting a
middle-dot drop of the liquid from the nozzle, and a large-dot
pulse-wave for jetting a large-dot drop of the liquid from the
nozzle, and the driving-pulse generator is adapted to generate,
based on the driving signal generated based on the third jetting
mode: a driving-pulse including only the small-dot pulse-wave when
the selected level data is the small-dot data, a driving-pulse
including only the middle-dot pulse-wave when the selected level
data is the middle-dot data, and a driving-pulse including only the
large-dot pulse-wave when the selected level data is the large-dot
data.
The third jetting mode is suitable for jetting with super-high
quality.
In addition, preferably, the pressure-changing unit has a
piezoelectric vibrating member.
The liquid may be an ink. In the case, the ink may include a
colorant and an organic solvent. A density of the colorant is
preferably 0.1 to 10% by weight. Furthermore preferably, the
colorant includes a pigment or a dye. Alternatively, the colorant
is preferably a pigment which has particles of 20 to 250 nm
diameter. In addition, preferably, a viscosity of the ink is 1 to
10 cps. A surface tension of the ink is preferably 25 to 60 mN/m.
The ink preferably includes water.
In addition, a controlling unit for controlling a liquid jetting
apparatus including a head having a nozzle, and a pressure-changing
unit for causing pressure of liquid in the nozzle to change in such
a manner that the liquid is jetted from the nozzle, comprises: a
jetting-mode setting unit for setting a selected jetting mode from
a plurality of jetting modes; a level-data setting unit for setting
a selected level data from a plurality of level data, based on a
jetting data; a driving-signal generator for generating a driving
signal, based on the selected jetting mode; a driving-pulse
generator for generating a driving pulse based on the selected
level data and the driving signal; and a main controller for
causing the pressure-changing unit to operate, based on the driving
pulse; wherein driving pulses generated based on a selected jetting
mode and respective selected level data are different from driving
pulses generated based on another selected jetting mode and the
respective selected level data.
A computer system can materialize the whole controlling unit or
only one or more components in the controlling unit.
This invention includes a storage unit capable of being read by a
computer, storing a program for materializing the controlling unit
in a computer system.
This invention also includes the program itself for materializing
the controlling unit in the computer system.
This invention includes a storage unit capable of being read by a
computer, storing a program including a command for controlling a
second program executed by a computer system including a computer,
the program is executed by the computer system to control the
second program to materialize the controlling unit.
This invention also includes the program itself including the
command for controlling the second program executed by the computer
system including the computer, the program is executed by the
computer system to control the second program to materialize the
controlling unit.
The storage unit may be not only a substantial object such as a
floppy disk or the like, but also a network for transmitting
various signals.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic perspective view of an ink-jetting printer of
a first embodiment according to the invention;
FIG. 2 is a sectional view of an example of a recording head;
FIG. 3 is a schematic block diagram for explaining an electric
structure of the ink-jetting printer;
FIG. 4 is a schematic block diagram for explaining an electric
driving structure of the recording head;
FIG. 5 is a diagram of an example of a driving signal;
FIG. 6 is diagrams for explaining driving pulses generated based on
the driving signal shown in FIG. 5;
FIG. 7 is a diagram of an example of a driving signal;
FIG. 8 is diagrams for explaining driving pulses generated based on
the driving signal shown in FIG. 7;
FIG. 9 is a diagram of an example of a driving signal;
FIG. 10 is diagrams for explaining driving pulses generated based
on the driving signal shown in FIG. 9;
FIG. 11 is a graph for explaining a relationship between volumes of
jetted ink and quality of a printed image;
FIG. 12 is a diagram of an example of a driving signal; and
FIG. 13 is diagrams for explaining driving pulses generated based
on the driving signal shown in FIG. 12.
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the invention will now be described in more detail
with reference to drawings.
Basic Structure
FIG. 1 is a schematic perspective view of an ink-jetting printer 1
as a liquid jetting apparatus of a first embodiment according to
the invention. In the ink-jetting printer 1, a carriage 2 is
slidably mounted on a guide bar 3. The carriage 2 is connected to a
timing belt 6, which goes around a driving pulley 4 and a free
pulley 5. The driving pulley 4 is connected to a rotational shaft
of a pulse motor 7. Thus, the carriage 2 can be reciprocated along
a direction of width of a recording paper 8 by driving the pulse
motor 7 (main scanning).
A recording head (head) 10 is mounted under the carriage 2. The
recording head 10 mounted under the carriage 2 is adapted to face
down to the recording paper 8.
As shown in FIG. 2, the recording head 10 mainly has: an ink
chamber 12 to which an ink is supplied from an ink cartridge 11
(see FIG. 1); a nozzle plate 14 provided with a plurality of (for
example 64) nozzles 13 in a sub-scanning direction; and a plurality
of pressure chambers 16 communicated with the plurality of nozzles
13, respectively. Each of the plurality of pressure chambers 16 is
adapted to be caused to expand and contract by deformation of a
piezoelectric vibrating member 15.
The ink chamber 12 and the plurality of pressure chambers 16 are
communicated via a plurality of ink supplying holes 17 and a
plurality of supply side communication holes 18, respectively. The
plurality of pressure chambers 16 and the plurality of nozzles 13
are communicated via a plurality of first nozzle side communication
holes 19 and a plurality of second nozzle side communication holes
20, respectively. Thus, for each of the plurality of nozzles 13, an
ink passage is formed from the ink chamber 12 to each of the
plurality of nozzles 13 via each of the plurality of pressure
chambers 16.
The nozzle plate 14 may be made of the same material as a
conventional known nozzle plate. For example, the material may be a
metal, ceramics, silicon, glass, plastic or the like. Preferably,
the material may be a single metal such as titanium, chromium,
iron, cobalt, nickel, copper, zinc, tin, gold or the like.
Alternatively, the material may be a compound metal (alloy) such as
nickel-phosphorus alloy, tin-copper-phosphorus alloy (phosphor
bronze), copper-zinc alloy, stainless steel, or the like. In
addition, the material may be polycarbonate, polysulfone, ABS resin
(co-polymerized acrylonitrile-butadiene-styrene), polyethylene
telephthalate, polyacetal, various photosensitive resin, or the
like.
The nozzle plate 14 in the embodiment is formed as an ink-repellent
nozzle plate 14. The ink-repellent nozzle plate 14 has a uniformly
formed ink-repellent film on a surface of a base plate. The
ink-repellent nozzle plate 14 is provided with the plurality of
nozzles 13, each of which is a through opening.
The through opening (nozzle 13) has a smaller diameter at an
outside surface of the nozzle plate 14 which faces the recording
paper 8, and a larger diameter at the side of the corresponding
second nozzle communication hole 20. Thus, an inside surface of the
through opening is funnel-like or conical. The ink-repellent film
is formed on at least the outside surface of the nozzle plate
14.
In the embodiment, each of the piezoelectric vibrating members 15
is adapted to cause each of the pressure chambers 16 to expand or
contract by distortion thereof. Thus, when the electric power
(potential) is supplied to a piezoelectric vibrating member 15, the
piezoelectric vibrating member 15 is charged and contracts in a
direction perpendicular to a direction of the electric field. Then,
a pressure chamber 16 corresponding to the piezoelectric vibrating
member 15 is caused to contract. When the electric charges are
discharged from the piezoelectric vibrating member 15, the
piezoelectric vibrating member 15 extends in the direction
perpendicular to the direction of the electric field. Then, a
pressure chamber 16 corresponding to the piezoelectric vibrating
member 15 is caused to expand.
That is, in the recording head 10, a volume of the pressure chamber
16 may be changed by the corresponding piezoelectric vibrating
member 15 charged or discharged. This may cause pressure of the ink
in the pressure chamber 16 to change, so that a drop of the ink may
be jetted from the corresponding nozzle 13.
Another type of piezoelectric vibrating member which may expand and
contract in a longitudinal direction thereof can be also used,
instead of the piezoelectric vibrating member 15 causing the
corresponding pressure chamber 16 to expand or contract by
distortion thereof. In the case, the corresponding pressure chamber
can expand by deformation of the piezoelectric vibrating member
when the piezoelectric vibrating member is charged, and can
contract by deformation of the piezoelectric vibrating member when
the piezoelectric vibrating member is discharged.
Suitable Ink
The ink stored in the ink cartridge 11 is a kind of ink suitable
for the ink-repellent nozzle plate 14. The ink may be aqueous type
or organic type. Preferably, the ink is aqueous. In addition,
preferably, the ink has a viscosity of 1 to 10 cps, more preferably
2.5 to 6 cps.
The ink may include a colorant such as a dye, a pigment, or the
like. The dye may be a direct dye, an acid dye, a food dye, a basic
dye, a reactive dye, or the like. The pigments may be any inorganic
pigment or any organic pigment.
As the dye, a black dye, a yellow dye, a magenta dye and a cyan dye
may be used.
The black dye may be C.I. Direct Black 17, C.I. Direct Black 19,
C.I. Direct Black 62, C.I. Direct Black 154, C.I. Food Black 2,
C.I. Reactive Black 5, C.I. Acid Black 52, C.I. Projet Fast Black
2, or the like.
The yellow dye may be C.I. Direct Yellow 11, C.I. Direct Yellow 44,
C.I. Direct Yellow 86, C.I. Direct Yellow 142, C.I. Direct Yellow
330, C.I. Acid Yellow 3, C.I. Acid Yellow 38, C.I. Basic Yellow 11,
C.I. Basic Yellow 51, C.I. Disperse Yellow 3, C.I. Disperse Yellow
5, C.I. Reactive Yellow 2, or the like.
The magenta dye may be C.I. Direct Red 227, C.I. Direct Red 23,
C.I. Acid Red 18, C.I. Acid Red 52, C.I. Basic Red 14, C.I. Basic
Red 39, C.I. Disperse Red 60, or the like.
The cyan dye may be C.I. Direct Blue 15, C.I. Direct Blue 199, C.I.
Direct Blue 168, C.I. Acid Blue 9, C.I. Acid Blue 40, C.I. Basic
Blue 41, C.I. Acid Blue 74, C.I. Reactive Blue 15, or the like.
The inorganic pigments include for example titanium oxide, iron
oxide and carbon black which is produced by a known method such as
a contact method, a furnace method or a thermal method.
In addition, the organic pigments include for example azo pigments
such as azo lake, water-insoluble azo pigments, condensed azo
pigments and chelate azo pigments; polycyclic pigments such as
phthalocyanine pigments, perylene pigments, perinone pigments,
anthraquinone pigments, quinacrideone pigments, dioxazine pigments,
thioindigo pigments, isoindolinone pigments and quinophethalone
pigments; dye chelates such as basic dye-type chelates and acidic
dye-type chelates; nitro pigments; nitroso pigments and aniline
black.
In detail, a yellow pigment may be C.I. Pigment Yellow 74, 109, 110
or 138. A magenta pigments may be C.I. Pigment Red 122, 202 or 209.
A cyan pigments may be C.I. Pigment Blue 15:3 or 60. A Black
pigment may be C.I. Pigment Black 7. An orange pigment may be C.I.
Pigment Orange 36 or 43. A green pigment may be C.I. Pigment Green
7 or 36.
Density of the colorant in the ink is preferably in the range of
0.1 to 10% by weight.
An average particle diameter of the pigments is preferably in the
range of 20 nm to 250 nm, more preferably 50 nm to 200 nm.
Although the following explanation is given for the ink including
the pigments, the explanation is applicable to the ink including
the dyes.
Any known polymeric dispersant consisting of natural polymers or
synthetic polymers, which has been conventionally used for
dispersing pigment in ink, or any known surface active agent can be
favorably used as a dispersant in the case.
The natural polymers may include for example proteins such as glue,
gelatin, albumin and casein; natural rubbers such as gum arabic and
tragacanth gum; glucosides such as saponin; alginic acid and
derivatives thereof such as propylene glycol alginate, triethanol
amine alginate and ammonium alginate; and cellulose derivatives
such as methyl cellulose, carboxymethyl cellulose, hydroxymethyl
cellulose and ethyl hydroxymethyl cellulose.
The synthetic polymers may include for example polyvinyl alcohols;
polyvinyl pyrrolidones; acrylic resins such as polyacrylic acid, an
acrylic acid-acrylonitrile copolymer, a potassium
acrylate-acrylonitrile copolymer, a vinyl acetate-acrylic acid
ester copolymer and an acrylic acid-acrylic acid alkyl ester
copolymer; styreneacrylic resins such as a stylene-acrylic acid
copolymer, a stylene-methacrylic acid copolymer, a
stylene-methacrylic acid-acrylic acid alkyl ester copolymer, a
stylene-.alpha.-methylstylene-acrylic acid copolymer and a
stylene-.alpha.-methylstylene-acrylic acid-acrylic acid alkyl ester
copolymer; a stylene-maleic acid copolymer; a stylene-maleic
anhydride copolymer; a vinylnaphthalene-acrylic acid copolymer;
vinyl acetate resin such as a vinyl acetate-ethylene copolymer, a
vinyl acetate-fatty acid vinyl ethylene copolymer, a vinyl
acetate-maleic acid ester copolymer, a vinyl acetate-crotonic acid
copolymer and a vinyl acetate-acrylic acid copolymer; and salts of
thereof.
In particular, polymers which comprises monomers having a
hydrophobic group and monomers having a hydrophilic group and
polymers which comprises monomers having both a hydrophobic group
and a hydrophilic group are preferable.
Preferred examples of the salts of these polymers may include
diethylamine, ammonia, ethylamine, triethylamine, propylamine,
isopropylamine, dipropylamine, butylamine, isobutylamine,
triethanolamine, diethanolamine, aminomethylpropanol and
morpholine. It is preferable that the weight average molecular
weight of these copolymers be from 3,000 to 30,000, more preferably
from 5,000 to 15,000.
The surface active agents may include for example anionic surface
active agents such as salts of a fatty acid, higher alkylsulfates,
salts of a higher alcohol sulfate ester, condensation products of a
higher fatty acid and amino acid, sulfosuccinates, naphthnates,
salts of a liquid fatty oil sulfate ester and alkyl allyl sulfate;
cationic surface active agents such as salts of fatty amides,
quaternary ammonium salts, sulfonium salts and phosphonium; and
nonionic surface active agents such as polyoxyethylene alkyl
esters, polyoxyethylene alkyl esters, sorbitan alkyl esters and
polyoxyethylene sorbitan alkyl esters. Surface tension of the ink
is preferably in the range of 25 to 60 mN/m, more preferably 28 to
40 mN/m.
A suitable amount of the dispersant is in the range of 0.06 to 3%
by weight, preferably 0.125 to 3% by weight, with respect to the
pigment.
In addition, it is preferable that the ink includes a or more
wetting agent. The wetting agents may include for example
diethylene glycol, polyethylene glycol, polypropylene glycol,
ethylene glycol, propylene glycol, butylene glycol, triethylene
glycol, 1,2,6-hexanetriol, thioglycol, hexylene glycol, glycerine,
trimethylolethane, trimethylolpropane, urea, 2-pyrrolidone,
N-methyl-2-pyrrolidone and 1,3-dimethyl-2-imidazalidinone. The
wetting agents having an ethylene oxide group are particularly
preferred, and diethylene glycol is most preferred. In addition to
the wetting agent, it is preferable to further add an organic
solvent having a low boiling point.
Preferred examples of such an organic solvent may include methanol,
ethanol, n-propanol, isopropanol, n-butanol, sec-butanol,
tert-butanol, isobutanol, n-pentanol, ethylene glycol monomethyl
ether, ethylene glycol monoethyl ether, diethylene glycol
monomethyl ether, diethylene glycol monoethyl ether, triethylene
glycol monomethyl ether and triethylene glycol monoethyl ether.
Monovalent alcohols are particularly preferred.
An amount of the wetting agent is preferably in the range of 0.5 to
40% by weight, more preferably 2 to 20% by weight with respect to
the ink. An amount of the organic solvent having a low boiling
point is preferably in the range of 0.5 to 10% by weight, more
preferably 1.5 to 6% by weight of the ink.
In addition, although no particular limitation is imposed on the
surface active agent in the case, preferable examples thereof may
include: anionic surface active agents such as sodium
dodecylbenzenesulfonate, sodium laurate, ammonium salts of
polyoxyethylene alkyl ether sulfate; and nonionic surface active
agents such as polyoxyethylene alkyl ether, polyoxyethylene alkyl
ester polyoxyethylene sorbitan fatty acid ester, polyoxyethylene
alkylphenyl ether, polyoxyethylene alkylamine polyoxyethylene
alkylamide. These surface active agents can be used either singly
or as a mixture of two or more. In addition, a surface active agent
consisting of acetyleneglycol or the like (olefine Y and sulfinole
82, 104, 440, 465, 485 and TG (made by Air Products and Chemicals
Inc.)) can be used.
The ink can contain optional additives in order to improve the
properties of the ink. Specific examples of such additives may
include a pH adjustor, a preservative and an antifungal agent.
The ink can be prepared by dispersing and mixing the
above-described components by a proper method. A preferable manner
is such that the components except an organic solvent and a
volatile component are mixed in a proper dispersion mixer such as a
ball mill, a sand mill, an atrittor, a roll mill, an agitator mill,
a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a jet
mill, an angmill, to obtain a homogeneous composition, and an
organic solvent and a volatile component are then added to this
composition. It is preferable to subject the thus obtained mixture
to filtration, preferably filtration using a metal filter, a
membrane filter or the like under a reduced or increased pressure,
or to centrifugal separation, in order to remove large particles
and foreign matters which tend to be a cause of obstruction in the
nozzle.
Electric Structure
In the printer 1 as described above, a drop of the ink may be
jetted from the recording head 10 synchronously with the main
scanning of the carriage 2, during a recording operation. A platen
34 may be rotated synchronously with the reciprocation of the
carriage 2 so that the recording paper 8 is fed in a feeding
(sub-scanning) direction. As a result, an image including
characteristics or the like is recorded on the recording paper 8,
based on recording data.
Then, an electric structure of the ink-jetting printer 1 is
explained. As shown in FIG. 3, the printer 1 has a printer
controller 23 and a printing engine 24.
The printer controller 23 has: an outside interface (outside I/F)
25; a RAM 26 for temporarily storing various data; a ROM 27 storing
a controlling program or the like; a main controller 28 including a
CPU or the like; a oscillating circuit 29 for generating a clock
signal (CK); a driving-signal generating circuit 30 for generating
driving signals (COM) for supplying to the recording head 10; and
an inside interface (inside I/F) 31 for transmitting the driving
signals, dot pattern data (bit map data) developed based on
printing data (recording data) or the like to the printing engine
24.
The outside I/F 25 is adapted to receive the printing data
consisting of character codes, graphic functions, image data or the
like, from a host computer (not shown) or the like. In addition,
the outside I/F 25 is adapted to output a busy signal (BUSY) and/or
an acknowledge signal (ACK) to the host computer or the like.
In addition, the outside I/F 25 in the embodiment is connected to
an interface unit 100 such as a keyboard, which may function as a
quality-mode setting unit (a jetting-mode setting unit) for setting
a quality mode (jetting mode) relative to recording accuracy to the
recording paper 8 (medium for recording).
The RAM 26 has a receiving buffer, an intermediate buffer, an
outputting buffer and a work memory (not shown). The receiving
buffer can temporarily store the printing data received via the
outside I/F 25. The intermediate buffer can store intermediate code
data converted by the main controller 28. The outputting buffer can
store dot pattern data. The dot pattern data mean printing data
obtained by decoding (translating) the intermediate code data (for
example level data).
The ROM 27 stores font data, graphic functions or the like as well
as the controlling program for conducting various data
processing.
The main controller 28 is adapted to conduct various controls
according to the controlling program stored in the ROM 27. For
example, the main controller 28 reads out the printing data in the
receiving buffer, converts the printing data into the intermediate
code data, and causes the intermediate buffer to store the
intermediate code data. In addition, the main controller 28
analyzes the intermediate code data read out from the intermediate
buffer, and develops (decodes) the intermediate code data into the
dot pattern data with reference to the font data and the graphic
functions or the like stored in the ROM 27. Then, the main
controller 28 conducts necessary decoration processes to the dot
pattern data, and causes the outputting buffer to store the dot
pattern data. In the case, each of the dot pattern data consists of
two bit data as a level data. That is, the main controller 28 may
function as a level-data setting unit.
After dot pattern data for one line, which correspond to one main
scanning of the recording head 10, are obtained, the dot pattern
data for the one line is outputted in turn from the outputting
buffer to the recording head 10 via the inside I/F 31. When the dot
pattern data for the one line is outputted from the outputting
buffer, the intermediate code data that have already been developed
are erased from the intermediate buffer. Then, the next
intermediate code data start to be developed.
In addition, the main controller 28 may function as a part of
timing signal generating unit, that is, supply latch signals (LAT)
and/or channel signals (CH) to the recording head 10 via the inside
I/F 31. The latch signals and/or the channel signals define
starting timings for supplying driving pulses, each of which forms
a part of a driving signal (COM).
However, the printing engine 24 has: a paper-feeding motor 35 as a
paper-feeding mechanism; the pulse motor 7 as a carriage-moving
mechanism; and an electric driving system 33 for the recording head
10. The paper-feeding motor 35 causes the platen 34 (see FIG. 1) to
rotate in order to feed the recording paper 8. The pulse motor 7
causes the carriage 2 to move via the timing belt 6.
As shown in FIG. 3, the electric driving system 33 for the
recording head 10 has: a shift-register circuit consisting of a
first shift-register 36 and a second shift-register 37; a latch
circuit consisting of a first latch-circuit 39 and a second
latch-circuit 40; a decoder 42; a controlling logic circuit 43; a
level shifter 44; a switching circuit 45; and the piezoelectric
vibrating members 15.
As shown in FIG. 4, the first shift-register 36 has a plurality of
first shift-register devices 36A to 36N, each of which corresponds
to each of the nozzles 13 of the recording head 10. Similarly, the
second shift-register 37 has a plurality of second shift-register
devices 37A to 37N, each of which corresponds to each of the
nozzles 13 of the recording head 10. The first latch-circuit 39 has
a plurality of first latch-circuit devices 39A to 39N, each of
which corresponds to each of the nozzles 13 of the recording head
10. Similarly, the second latch-circuit 40 has a plurality of
second latch-circuit devices 40A to 40N, each of which corresponds
to each of the nozzles 13 of the recording head 10. The decoder 42
has a plurality of decoder devices 42A to 42N, each of which
corresponds to each of the nozzles 13 of the recording head 10. The
switching circuit 45 has a plurality of switching circuit devices
45A to 45N, each of which corresponds to each of the nozzles 13 of
the recording head 10. Each of the piezoelectric vibrating members
15 corresponds to each of the nozzles 13. Thus, the piezoelectric
vibrating members 15 are also designated as piezoelectric vibrating
members 15A to 15N.
According to the electric driving system 33, the recording head 10
can jet a drop of the ink, based on the printing data (level data)
from the printer controller 23. The printing data 30 (SI) from the
printer controller 23 are transmitted in a serial manner to the
first shift-register 36 and the second shift-register 37 via the
inside I/F 31, synchronously with the clock signal (CK) from the
oscillating circuit 29.
The printing data from the printer controller 23 are data
consisting of 2 bits as described above. In detail, four levels
consisting of no recording, a small dot, a middle dot and a large
dot are represented by the two bit data. That is, the level data of
no recording is represented by "00", the level data of the small
dot is represented by "01", the level data of the middle dot is
represented by "10", and the level data of the large dot is
represented by "11".
The printing data are set for each of printing dots, that is, each
of the nozzles 13. Then, the lower bits of the printing data for
all the nozzles 13 are inputted in the first shift-register devices
36A to 36N, respectively. Similarly, the upper bits of the printing
data for all the nozzles 13 are inputted in the second
shift-register devices 37A to 37N, respectively.
As shown in FIGS. 3 and 4, the first shift-register devices 36A to
36N are electrically connected to the first latch-circuit devices
39A to 39N, respectively. Similarly, the second shift-register
devices 37A to 37N are electrically connected to the second
latch-circuit devices 40A to 40N, respectively. When the latch
signals (LAT) from the printer controller 23 are inputted to the
first and the second latch-circuit devices 39A to 39N and 40A to
40N, the first latch-circuit devices 39A to 39N latch the lower
bits of the printing data, and the second latch-circuit devices 40A
to 40N latch the upper bits of the printing data, respectively.
As described above, a circuit unit consisting of the first
shift-register 36 and the first latch-circuit 39 may function as a
storing circuit. Similarly, a circuit unit consisting of the second
shift-register 36 and the second latch-circuit 39 may also function
as a storing circuit. That is, these storing circuit can
temporarily store the printing data (level data) before inputted to
the decoder 42.
The printing data latched in the latch-circuits 39 and 40 are
supplied to the decoder 42, that is, the decoder devices 42A to
42N. The decoder devices 42A to 42N decode (translate) the printing
data (level data) of the two bits into pulse-selecting data,
respectively. Each of the pulse-selecting data has a plurality of
bits equal to or more than the level data, each of the plurality of
bits corresponds to a pulse-wave forming a part of the driving
signal (COM). Then, depending on each of the bits of the pulse
selecting data ("0" or "1"), each of the pulse-waves may be
supplied or not to the piezoelectric vibrating member 15. The
driving signal (COM) and the pulse-waves will be described in
detail hereafter.
In addition, timing signals from the controlling logic circuit 43
are also inputted to the decoder 42 (decoder devices 42A to 42N).
The controlling logic circuit 43 may function as a timing-signal
generator together with the main controller 28, in order to
generate the timing signals based on the latch signals (LAT) and
the channel signals (CH).
The pulse-selecting data translated by the decoder 42 (decoder
devices 42A to 42N) are inputted to the level shifter 44
(respective level shifter devices 44A to 44N) in turn from an
uppermost bit thereof to a lowermost bit thereof at respective
timings defined by the timing signals. For example, the uppermost
bit of the pulse-selecting data is inputted to the level shifter 44
at the first timing of a recording period, and the second uppermost
bit of the pulse-selecting data is inputted to the level shifter 44
at the second timing.
The level shifter 44 is adapted to function as a voltage amplifier.
For example, when a bit of the pulse-selecting data is "1", the
level shifter 44 raises the datum "1"to a voltage of several decade
volts that can drive the switching circuit 45 (respective switching
circuit devices 45A to 45N).
The raised datum is applied to the switching circuit 45, which may
function as a driving-pulse generator and a controlling body. That
is, the switching circuit 45 selects and generates one or more
driving pulses from the driving signal (COM), based on the pulses
electing data generated by translating the printing data. The
generated one or more driving pulses are supplied to the
piezoelectric vibrating member 15. For the purpose, input terminals
of the switching circuit devices 45A to 45N are adapted to be
supplied the driving signal (COM) from the driving-signal generator
30, and output terminals of the switching circuit devices 45A to
45N are connected to the piezoelectric vibrating members 15A to
15N, respectively.
Each of the switching devices 45A to 45N is controlled by the
pulse-selecting data. That is, a switching device of 45A to 45N is
closed (connected) when a bit of the pulse-selecting data is 1.
Then, the corresponding driving pulse is supplied to the
corresponding piezoelectric vibrating member 15. Thus, an
electric-potential level of the piezoelectric vibrating member 15
is changed.
On the other hand, when a bit of the pulse-selecting data is "0", a
level shifter device of 44A to 44N does not output an electric
signal for operating the corresponding switching circuit device of
45A to 45N. Then, the switching circuit device is not connected, so
that the corresponding driving pulse (pulse-wave) is not supplied
to the corresponding piezoelectric vibrating member 15. While a bit
of the pulse-selecting data is "0", the piezoelectric vibrating
member 15 holds a previous electric charges. That is, an
electric-potential level of the piezoelectric vibrating member 15
is maintained.
That is, the pulse-selecting data function as a rectangular-pulse
row corresponding to a period of the driving signal. The driving
pulse is an AND signal of the rectangular-pulse row and the driving
signal.
Then, the driving signal (COM) generated by the driving-signal
generator 30 and a control of jetting one or more drops of the ink
by means of the driving signal are explained in detail. The
driving-signal generator 30 is adapted to generate a plurality of
driving signals based on respective quality modes (a first quality
mode, a second quality mode and a third quality mode). In the
embodiment, volumes of the ink jetted from the nozzle based on the
respective driving signals of the respective quality modes are
different with respect to a same printing data (level data).
Characteristics of the Respective Quality Modes
Characteristics of the respective quality modes are explained. The
first quality mode is a mode for recording at a relatively high
speed and with a relatively low quality. The second quality mode is
a mode for recording at a relatively middle speed and with a
relatively middle quality. The third quality mode is a mode for
recording at a relatively low speed and with a relatively high
quality.
FIG. 5 is a diagram of a driving signal of the first quality mode.
FIG. 6 is diagrams for explaining driving pulses generated based on
the driving signal of the first quality mode. FIG. 7 is a diagram
of a driving signal of the second quality mode. FIG. 8 is diagrams
for explaining driving pulses generated based on the driving signal
of the second quality mode. FIG. 9 is a diagram of a driving signal
of the third quality mode. FIG. 10 is diagrams for explaining
driving pulses generated based on the driving signal of the third
quality mode.
Driving Signal A
At first, the driving signal A defined by the first quality mode is
explained with reference to the FIG. 5. As shown in FIG. 5, the
driving signal A is a periodical signal having a recording period
TC. The recording period TC is divided into a part T1 including a
first pulse-wave PS21, a part T2 including a second pulse-wave PS22
and a part T3 including a third pulse-wave PS23. The first
pulse-wave PS21, the second pulse-wave PS22 and the third
pulse-wave PS23 are connected in a series manner. In the case, the
recording period TC corresponds to a frequency of 8.57.times.3 kHz.
The first pulse-wave PS21 is adapted to function as a first driving
pulse DP6. The second pulse-wave PS22 is adapted to function as a
second driving pulse DP7. The third pulse-wave PS23 is adapted to
function as a third driving pulse DP9.
In the case, the first driving pulse DP6 (the first pulse-wave
PS21), the second driving pulse DP7 (the second pulse-wave PS22)
and the third driving pulse DP8 (the first pulse-wave PS23) have a
common wave-pattern (wave form). Each of the first driving pulse
DP6, the second driving pulse DP7 and the third driving pulse DP8
can jet a drop of the ink alone.
That is, each of the pulse-waves (driving pulses DP6, DP7 and DP8)
includes: a first discharging element P51 falling from a middle
electric potential VM to a lowest electric potential VL at an
incline .theta.31, a first holding element P52 maintaining the
lowest electric potential VL for a very short time, a first
charging element P53 rising from the lowest electric potential VL
to a highest electric potential VH at a steep incline .theta.32
within a very short time, a second holding element P54 maintaining
the highest electric potential VH for a time, and a second
discharging element P55 falling from the highest electric potential
VH to the middle electric potential VM at an incline .theta.33.
When each of the pulse-waves (driving pulses) is supplied to the
piezoelectric vibrating member 15, a drop of the ink, whose volume
corresponds to a small dot, is jetted from the nozzle 13.
In detail, when the first discharging element P51 is supplied to
the piezoelectric vibrating member 15, the piezoelectric vibrating
member 15 is discharged from the middle electric potential VM.
Then, the corresponding pressure chamber 16 is caused to expand
from a standard volume thereof to a maximum volume thereof. Then,
by the first charging element P53, the pressure chamber 16 is
caused to rapidly contract to a minimum volume there of. Such a
contracting state of the pressure chamber 16 is maintained while
the second holding element P54 is supplied to the piezoelectric
vibrating member 15. The rapid contraction and the keeping of the
contracting state of the pressure chamber 16 raise a pressure of
the ink in the pressure chamber 16so rapidly that a drop of the ink
is jetted from the nozzle 13. A volume of the jetted drop of the
ink is for example about 13 pL. Then, by the second discharging
element P55, the pressure chamber 16 is caused to expand back to an
original state thereof in order to settle down a vibration of a
meniscus of the ink at the nozzle 13 within a short time.
As shown in FIG. 6, according to the first quality mode, a level
control can be achieved by increasing or decreasing the number of
the pulse-waves (driving pulses) to supply to the piezoelectric
vibrating member 15. For example, when only one pulse-wave is
supplied to the piezoelectric vibrating member 15, a small dot of
the ink is formed for recording. When only two pulse-waves are
supplied to the piezoelectric vibrating member 15, a middle dot of
the ink is formed for recording. When all the three pulse-waves are
supplied to the piezoelectric vibrating member 15, a large dot of
the ink is formed for recording.
Driving Signal B
Next, the driving signal B defined by the second quality mode is
explained with reference to the FIG. 7. As shown in FIG. 7, the
driving signal B is a periodical signal having a recording period
TA. The recording period TA is divided into a part T1 including a
first pulse-wave PS1 and a part T2 including a second pulse-wave
PS2. The first pulse-wave PS1 and the second pulse-wave PS2 are
connected in a series manner. The first pulse-wave PS1 is adapted
to function as a small-dot driving pulse DP1 for jetting a
small-dot drop of the ink from the nozzle 13 (a first small-dot
driving pulse). The second pulse-wave PS2 is adapted to function as
a middle-dot driving pulse DP2 for jetting a middle-dot drop of the
ink from the nozzle 13 (a first middle-dot driving pulse).
The first pulse-wave PS1 (small-dot driving pulse DP1) includes: a
first charging element P1 rising from a middle electric potential
VM to a highest electric potential VH at a relatively gentle
incline .theta.1, a first holding element P2 maintaining the
highest electric potential VH for a predetermined time, a first
discharging element P3 falling from the highest electric potential
VH to a lowest electric potential VL at a predetermined incline
.theta.2, a second holding element P54 maintaining the lowest
electric potential VL for a short time, a second charging element
P5 rising from the lowest electric potential VL to the highest
electric potential VH at a steep incline .theta.3 within a very
short time, a third holding element P6 maintaining the highest
electric potential VH for a very short time, a second discharging
element P7 falling from the highest electric potential VH to a
second middle electric potential VM2 at a incline .theta.4 within a
very short time, the second middle electric potential VM2 being set
between the middle electric potential VM and the lowest electric
potential VL, a fourth holding element P8 maintaining the second
middle electric potential VM2 for a predetermined time, and a third
charging element P9 rising back to the middle electric potential VM
at a incline .theta.5.
In the first pulse-wave PS1, the inclines .theta.1, .theta.2 and
.theta.5 are set in such a manner that no drop of the ink may be
jetted, respectively.
The second pulse-wave PS2 (middle-dot driving pulse DP2) includes:
a third discharging element P11 falling from the middle electric
potential VM to the lowest electric potential VL at a incline
.theta.6, a fifth holding element P12 maintaining the lowest
electric potential VL for a predetermined time, a fourth charging
element P13 rising from the lowest electric potential VL to the
highest electric potential VH at a steep incline .theta.7, a sixth
holding element P14 maintaining the highest electric potential VH
for a predetermined time, and a fourth discharging element P15
falling from the highest electric potential VH to the middle
electric potential VM at an incline .theta.8.
In the second pulse-wave PS2, the incline .theta.6 is set in such a
manner that no drop of the ink may be jetted.
One or more micro-vibrating pulse-waves for micro-vibrating the
meniscus of the ink at the nozzle 13 can be inserted between the
first pulse-wave PSI and the second pulse-wave PS2, although not
included in the driving signal B of the embodiment.
When the first pulse-wave PSI is supplied to the piezoelectric
vibrating member 15, a drop of the ink, whose volume corresponds to
a small dot, is jetted from the nozzle 13.
In detail, when the first charging element P1 is supplied to the
piezoelectric vibrating member 15, the piezoelectric vibrating
member 15 is charged from the middle electric potential VM. Then,
the corresponding pressure chamber 16 is caused to gradually
contract from a standard volume thereof (corresponding to the
middle electric potential VM) to a minimum volume thereof
(corresponding to the highest electric potential VH). Such a
contracting state of the pressure chamber 16 is maintained while
the first holding element P2 is supplied to the piezoelectric
vibrating member 15. Then, by the first discharging element P3, the
pressure chamber 16 is caused to expand to a maximum volume thereof
(corresponding to the lowest electric potential VL).
Then, by the second charging element P5, the pressure chamber 16 is
caused to rapidly contract from the maximum volume thereof to the
minimum volume thereof. Such a rapid contraction of the pressure
chamber 16 raises a pressure of the ink in the pressure chamber 16
so that a drop of the ink is jetted from the nozzle 13. As the
second charging element P5 is supplied within a very short time,
the pressure chamber 16 is caused to expand by the second
discharging element P7 immediately. Thus, a volume of the jetted
drop of the ink is for example as little as 3 to 9 pL.
Then, by the fourth holding element P8, the pressure chamber 16
maintains a volume corresponding to the second middle electric
potential VM2 for a predetermined time. Then, by the third
discharging element P9, the pressure chamber 16 is caused to
contract back in order to settle down a vibration of a meniscus of
the ink at the nozzle 13 within a short time.
When the second pulse-wave PS2 is supplied to the piezoelectric
vibrating member 15, a middle-dot drop of the ink, whose volume
corresponds to a middle dot, is jetted from the nozzle 13.
In detail, when the third discharging element P11 is supplied to
the piezoelectric vibrating member 15, the piezoelectric vibrating
member 15 is discharged from the middle electric potential VM.
Then, the corresponding pressure chamber 16 is caused to gradually
expand from the standard volume thereof to the maximum volume
thereof. Then, by the fifth holding element P12, the pressure
chamber 16 maintains the maximum volume thereof corresponding to
the lowest electric potential VL for a short time. Then, by the
fourth charging element P13, the pressure chamber 16 is caused to
rapidly contract to the minimum volume thereof corresponding to the
highest electric potential VH. Such a rapid contraction of the
pressure chamber 16 raises a pressure of the ink in the pressure
chamber 16 so that a drop of the ink is jetted from the nozzle 13.
Then, the pressure chamber 16 maintains the minimum volume thereof
while the sixth holding element P14 is supplied to the
piezoelectric vibrating member 15. Thus, a volume of the jetted
drop of the ink is for example as much as 9 to 15 pL. Then, by the
fourth discharging element P15, the pressure chamber 16 is caused
to expand back to the standard volume thereof in order to settle
down a vibration of a meniscus of the ink at the nozzle 13 within a
short time.
As shown in FIG. 8, according to the recording mode, a large dot
can be recorded by supplying both the first pulse-wave PS1 and the
second pulse-wave PS2 for one dot.
As described above, the driving signal B include only the two
pulse-waves of the first pulse-wave PS1 (small-dot driving pulse
DP1) and the second pulse-wave PS2 (middle-dot driving pulse DP2).
Thus, the recording period TA can be set relatively short. Thus, it
is possible to shorten a time necessary to record one dot. Thus,
recording by the second quality mode can be conducted at a higher
speed with a relatively high quality.
Driving Signal C
Next, the driving signal C defined by the third quality mode is
explained with reference to the FIG. 9. As shown in FIG. 9, the
driving signal C is a periodical signal having a recording period
TB. The recording period TB is divided into a part T1 including a
first pulse-wave PS11, a part T2 including a second pulse-wave
PS12, a part TS1 including a first connecting element CP1, a part
T3 including a third pulse-wave PS13, a part T4 including a fourth
pulse-wave PS14, a part T5 including a fifth pulse-wave PS15, a
part TS2 including a second connecting element CP2, a part T6
including a sixth pulse-wave PS16, a part TS3 including a third
connecting element CP3, and a part T7 including a seventh
pulse-wave PS17. The first pulse-wave PS1, the second pulse-wave
PS12, the first connecting element CP1, the third pulse-wave PS13,
the fourth pulse-wave PS14, the fifth pulse-wave PS15, the second
connecting element CP2, the sixth pulse-wave PS16, the third
connecting element CP3 and the seventh pulse-wave PS17 are
connected in a series manner.
Each of the connecting elements CP1, CP2 and CP3 is an element
connecting an electric-potential level of the previous pulse-wave
and an electric-potential level of the next pulse-wave. The
connecting elements CP1, CP2 and CP3 are not supplied to the
piezoelectric vibrating member 15.
As shown in FIG. 9, in the third quality mode, the first pulse-wave
PS11 is adapted to function as a first micro-vibrating pulse for
micro-vibrating the meniscus of the ink at the nozzle 13. The
second pulse-wave PS12 is adapted to function as a part of a
small-dot driving pulse DP3 for jetting a small-dot drop of the ink
from the nozzle 13. The third pulse-wave PS13 is adapted to
function as a middle-dot driving pulse DP4 for jetting a middle-dot
drop of the ink from the nozzle 13. The fourth pulse-wave PS14 is
adapted to function as a part of a large-dot driving pulse DP5 for
jetting a large-dot drop of the ink from the nozzle 13 or as a part
of a second micro-vibrating pulse. The fifth pulse-wave PS15 is
adapted to function as a part of the second micro-vibrating pulse
to form the second micro-vibrating pulse together with the fourth
pulse-wave PS14. The sixth pulse-wave PS16 is adapted to function
as a part of the small-dot driving pulse DP3 to form the small-dot
driving pulse DP3 together with the second pulse-wave PS12. The
seventh pulse-wave PS17 is adapted to function as a part of the
large-dot driving pulse DP5 to form the large-dot driving pulse DP5
together with the fourth pulse-wave PS14.
That is, as shown in FIG. 10, when the second pulse-wave PS12 and
the sixth pulse-wave PS16 are picked out from the driving signal C,
the small-dot driving pulse DP3 (a second small-dot driving pulse)
is generated. Similarly, when the third pulse-wave PS13 is picked
out from the driving signal C, the middle-dot driving pulse DP4 (a
second middle-dot driving pulse) is generated. Similarly, when the
fourth pulse-wave PS14 and the seventh pulse-wave PS17 are picked
out from the driving signal C, the large-dot driving pulse DP5 is
generated.
The first micro-vibrating pulse is generated when the first
pulse-wave PS11 is picked out from the driving signal C. The second
micro-vibrating pulse is generated when the fourth pulse-wave PS14
and the fifth pulse-wave PS15 are picked out from the driving
signal C.
As shown in FIGS. 9 and 10, the small-dot driving pulse DP3
includes: a first charging element P21 rising from a middle
electric potential VM to a highest electric potential VH at a
relatively gentle incline .theta.11, a first holding element P22
maintaining the highest electric potential VH for a relatively long
time, a first discharging element P23 falling from the highest
electric potential VH to a lowest electric potential VL at a steep
incline .theta.12, a second holding element P24 maintaining the
lowest electric potential VL for a short time, a second charging
element P25 rising from the lowest electric potential VL to a
second highest electric potential VH2 at a steep incline .theta.13,
the second highest electric potential VH2 being set between the
middle electric potential VM and the highest electric potential VH,
a third holding element P26 maintaining the second highest electric
potential VH2 for a very short time, a second discharging element
P27 falling from the second highest electric potential VH2 to a
second middle electric potential VM2 at a steep incline .theta.14,
the second middle electric potential VM2 being set between the
middle electric potential VM and the lowest electric potential VL,
a fourth holding element P28 maintaining the second middle electric
potential VM2 for a very short time, a third charging element P29
rising from the second middle electric potential VM2 to a third
highest electric potential VH3 at a steep incline .theta.15, the
third highest electric potential VH3 being set slightly lower than
the second highest electric potential VH2, a fifth holding element
P30 maintaining the third highest electric potential VH3 for a
short time, and a third discharging element P31 falling back from
the third highest electric potential VH3 to the middle electric
potential VM at a incline .theta.16.
When the small-dot driving pulse DP3 is supplied to the
piezoelectric vibrating member 15, a small-dot drop of the ink,
whose volume corresponds to a small dot, is jetted from the nozzle
13.
In detail, when the first charging element P21 is supplied to the
piezoelectric vibrating member 15, the piezoelectric vibrating
member 15 is charged from the middle electric potential VM. Then,
the corresponding pressure chamber 16 is caused to gradually
contract from a standard volume thereof (corresponding to the
middle electric potential VM) to a minimum volume thereof
(corresponding to the highest electric potential VH). The pressure
chamber 16 maintains the minimum volume thereof while the first
holding element P22 is supplied to the piezoelectric vibrating
member 15. Then, the pressure chamber 16 is caused to rapidly
expand by the first discharging element P23, to contract again by
the second charging element P25, and to expand again by the second
discharging element P27. Such a series of contractions and
expansions of the pressure chamber 16 causes a pressure of the ink
in the pressure chamber 16 to change so that a drop of the ink is
jetted from the nozzle 13. A volume of the jetted drop of the ink
is as little as 0.5 to 4 pL. Then, the third charging element P29,
the fifth holding element P30 and the third discharging element P31
are supplied to the piezoelectric vibrating member 15 in turn.
Thus, the pressure chamber 16 is caused to contract and expand back
in order to settle down a vibration of a meniscus of the ink at the
nozzle 13 within a short time after the drop of the ink is
jetted.
The middle-dot driving pulse DP4 includes: a fourth discharging
element P32 falling from the middle electric potential VM to the
lowest electric potential VL at a incline .theta.17, a sixth
holding element P33 maintaining the lowest electric potential VL
for a time, a fourth charging element P34 rising from the lowest
electric potential VL to the second highest electric potential VH2
at a steep incline .theta.18, a seven holding element P35
maintaining the second highest electric potential VH2 for a very
short time, a fifth discharging element P36 falling from the second
highest electric potential VH2 to the second middle electric
potential VM2 at a steep incline .theta.19, an eighth holding
element P37 maintaining the second middle electric potential VM2
for a very short time, a fifth charging element P38 rising from the
second middle electric potential VM2 to the third highest electric
potential VH3 at a steep incline .theta.20, a ninth holding element
P39 maintaining the third highest electric potential VH3 for a
short time, and a sixth discharging element P40 falling back from
the third highest electric potential VH3 to the middle electric
potential VM at a incline .theta.21.
When the middle-dot driving pulse DP4 is supplied to the
piezoelectric vibrating member 15, a middle-dot drop of the ink,
whose volume corresponds to a middle dot, is jetted from the nozzle
13.
In detail, when the fourth discharging element P32 is supplied to
the piezoelectric vibrating member 15, the piezoelectric vibrating
member 15 is discharged from the middle electric potential VM.
Then, the corresponding pressure chamber 16 is caused to expand
from the standard volume thereof to the maximum volume thereof.
Then, the pressure chamber 16 is caused to contract by the fourth
charging element P34, and to expand again by the fifth discharging
element P36. Such a series of expansions and contraction of the
pressure chamber 16 causes a pressure of the ink in the pressure
chamber 16 to change so that a middle-dot drop of the ink is jetted
from the nozzle 13. A volume of the jetted middle-dot drop of the
ink is as much as 5 to 10 pL. Then, the fifth charging element P38,
the ninth holding element P39 and the sixth discharging element P40
are supplied to the piezoelectric vibrating member 15 in turn.
Thus, the pressure chamber 16 is caused to contract and expand back
in order to settle down a vibration of a meniscus of the ink at the
nozzle 13 within a short time after the drop of the ink is
jetted.
The large-dot driving pulse DP5 includes: a seventh discharging
element P41 falling from the middle electric potential VM to a
third middle electric potential VM3 at a incline .theta.22, the
third middle electric potential VH3 being set between the middle
electric potential VM and the second middle electric potential VM2,
a tenth holding element P42 maintaining the third middle electric
potential VM3 for a relatively long time, an eighth discharging
element P43 falling from the third middle electric potential VM3 to
the lowest electric potential VL at a incline .theta.23, a eleventh
holding element P44 maintaining the lowest electric potential VL
for a predetermined time, a sixth charging element P45 rising from
the lowest electric potential VL to the second highest electric
potential VH2 at a steep incline .theta.24, a twelfth holding
element P46 maintaining the second highest electric potential VH2
for a predetermined time, and a ninth discharging element P47
falling back from the second highest electric potential VH2 to the
middle electric potential VM at a incline .theta.25.
When the large-dot driving pulse DP5 is supplied to the
piezoelectric vibrating member 15, a large-dot drop of the ink,
whose volume corresponds to a large dot, is jetted from the nozzle
13.
In detail, when the seventh discharging element P41 is supplied to
the piezoelectric vibrating member 15, the piezoelectric vibrating
member 15 is discharged from the middle electric potential VM.
Then, the corresponding pressure chamber 16 is caused to expand a
little from the standard volume thereof. The pressure chamber 16
maintains the little expanded state thereof while the tenth holding
element P42 is supplied to the piezoelectric vibrating member 15.
Then, the pressure chamber 16 is caused to expand to the maximum
volume thereof by the eighth discharging element P43. The pressure
chamber 16 maintains the maximum volume thereof for a short time,
that is, while the eleventh holding element P44 is supplied to the
piezoelectric vibrating member 15. Then, the pressure chamber 16 is
caused to rapidly contract by the sixth charging element P45. Then,
the pressure chamber 16 maintains such a contracting state thereof
for a short time, that is, while the twelfth holding element P46 is
supplied to the piezoelectric vibrating member 15. By supplying the
sixth charging element P45 and the twelfth holding element P46, a
pressure of the ink in the pressure chamber 16 is rapidly raised,
and the contracting state of the pressure chamber 16 is maintained
for the short time. Thus, a large-dot drop of the ink is jetted
from the nozzle 13, whose volume is as much as 10 to 20 pL. Then,
the ninth discharging element P47 is supplied to the piezoelectric
vibrating member 15. Thus, the pressure chamber 16 is caused to
expand back in order to settle down a vibration of a meniscus of
the ink at the nozzle 13 within a short time after the drop of the
ink is jetted.
As described above, the driving signal C include the small-dot
driving pulse DP3, the middle-dot driving pulse DP4 and the
large-dot driving pulse DP5 in such a manner that the driving
pulses partly overlap. In the driving signal C, for each of the
elements forming the driving pulses, the respective inclinations,
the supplying time or the like can be changed. Thus, the
pulse-waves for the driving pulses are formed or modified
relatively freely. Thus, volumes of the ink jetted by the
respective driving pulses can be easily changed or adjusted. That
is, a plurality of dot-sizes can be recorded by respective minutely
controlled volumes of the ink. Thus, recording by the third quality
mode can be conducted with a extremely high quality.
Pulse-selecting Data
Then, in the embodiment, the pulse-selecting data generated based
on the small-dot dot-pattern data (level data 01), the middle-dot
dot-pattern data (level data 10) and the large-dot dot-pattern data
(level data 11) are explained in detail.
When the driving signal A shown in FIGS. 5 and 6 is used (the first
quality mode), a level control can be conducted by increasing or
decreasing the number of the pulse-waves (driving pulses) to supply
to the piezoelectric vibrating member 15. For example, when only
one pulse-wave is supplied to the piezoelectric vibrating member
15, a small dot of the ink is formed for recording. When only two
pulse-waves are supplied to the piezoelectric vibrating member 15,
a middle dot of the ink is formed for recording. When all the three
pulse-waves are supplied to the piezoelectric vibrating member 15,
a large dot of the ink is formed for recording.
In the case, the decoder 42 generates pulse-selecting data
consisting of three bits, based on the small-dot dot-pattern data
(level data 01), the middle-dot dot-pattern data (level data 10)
and the large-dot dot-pattern data (level data 11),
respectively.
Each of the three bits corresponds to each of the pulse-waves. That
is, an uppermost bit of the pulse-selecting data corresponds to the
first pulse-wave PS21 (the first driving pulse DP6). A second
uppermost bit of the pulse-selecting data corresponds to the second
pulse-wave PS22 (the second driving pulse DP7). A lowermost bit of
the pulse-selecting data corresponds to the third pulse-wave PS23
(the third driving pulse DP8).
In the case, the pulse-selecting data generated based on the
small-dot dot-pattern data (level data 01) is "010". Similarly, the
pulse-selecting data generated based on the middle-dot dot-pattern
data (level data 10) is "101", and the pulse-selecting data
generated based on the large-dot dot-pattern data (level data 11)
is "111".
When the uppermost bit of the pulse-selecting data is "1", the
switching circuit 45 (driving-pulse generator) is closed
(connected) from a first timing signal (LAT signal), which is
generated when the part T1 of the period TC starts, to a second
timing signal (CH signal), which is generated when the part T2 of
the period TC starts. In addition, when the second uppermost bit of
the pulse-selecting data is "1", the switching circuit 45 is closed
from the second timing signal to a third timing signal (CH signal),
which is generated when the part T3 of the period TC starts.
Similarly, when the lowermost bit of the pulse-selecting data is
"1", the switching circuit 45 is closed from the third timing
signal to a timing signal (LAT signal) which is generated when the
part T1 of the next period TC starts.
Thus, based on the small-dot dot-pattern data, only the second
driving pulse DP7 is supplied to the corresponding piezoelectric
vibrating member 15. Similarly, based on the middle-dot dot-pattern
data, only the first driving pulse DP6 and the third driving pulse
DP8 are supplied to the corresponding piezoelectric vibrating
member 15. In addition, based on the large-dot dot-pattern data,
all the first driving pulse DP6, the second driving pulse DP7 and
the third driving pulse DP8 are supplied to the corresponding
piezoelectric vibrating member 15 in succession.
As a result, correspondingly to the small-dot dot-pattern data, one
small-dot drop of the ink is jetted from the nozzle 13. The volume
of the jetted drop of the ink is 13 pL. Thus, a small dot is formed
on the recording paper 8. Correspondingly to the middle-dot
dot-pattern data, two small-dot drops of the ink are jetted from
the nozzle 13. The volume of the jetted drops of the ink is 26
(13.times.2) pL in total. Thus, a middle dot is formed on the
recording paper 8. Correspondingly to the large-dot dot-pattern
data, three small-dot drops of the ink are jetted from the nozzle
13. The volume of the jetted drops of the ink is 39 (13.times.3) pL
in total. Thus, a large dot is formed on the recording paper 8.
As described above, in the first mode, the pulse-selecting data
consists of the three bits. Thus, the driving pulse can be
generated at a relatively high speed. Thus, recording by the first
mode can be conducted at a high speed. In addition, since the
volume of 39 pL of the ink is jetted for a large dot in one path,
recording by the first mode can be conducted at a further higher
speed. On the other hand, since the middle dot and the large dot
are formed by combinations of the independently jetted small-dot
drops of the ink, quality of a recorded image is inferior to the
second mode and the third mode.
Next, the case wherein the driving signal B shown in FIGS. 7 and 8
is used (the second quality mode) is explained.
In the case, the decoder 42 generates pulse-selecting data
consisting of two bits, based on the small-dot dot-pattern data
(level data 01), the middle-dot dot-pattern data (level data 10)
and the large-dot dot-pattern data (level data 11),
respectively.
Each of the two bits corresponds to each of the pulse-waves. That
is, an upper bit of the pulse-selecting data corresponds to the
first pulse-wave PS1 (the small-dot driving pulse DP1). A lower bit
of the pulse-selecting data corresponds to the second pulse-wave
PS2 (the middle-dot driving pulse DP2).
In the case, the pulse-selecting data generated based on the
small-dot dot-pattern data (level data 01) is "10". Similarly, the
pulse-selecting data generated based on the middle-dot dot-pattern
data (level data 10) is "01", and the pulse-selecting data
generated based on the large-dot dot-pattern data (level data 11)
is "11".
When the upper bit of the pulse-selecting data is "1", the
switching circuit 45 (driving-pulse generator) is closed
(connected) from a first timing signal (LAT signal), which is
generated when the part T1 of the period TA starts, to a second
timing signal (CH signal), which is generated when the part T2 of
the period TA starts. In addition, when the lower bit of the
pulse-selecting data is "1", the switching circuit 45 is closed
from the second timing signal to a timing signal (LAT signal) which
is generated when the part T1 of the next period TA starts.
Thus, based on the small-dot dot-pattern data, only the first
pulse-wave PS1 is supplied to the corresponding piezoelectric
vibrating member 15. Similarly, based on the middle-dot dot-pattern
data, only the second pulse-wave PS2 is supplied to the
corresponding piezoelectric vibrating member 15. In addition, based
on the large-dot dot-pattern data, both the first pulse-wave PS1
and the second pulse-wave PS2 are supplied to the corresponding
piezoelectric vibrating member 15 in succession.
As a result, correspondingly to the small-dot dot-pattern data, a
small-dot drop of the ink is jetted from the nozzle 13. The volume
of the jetted small-dot drop of the ink is 3 to 9 pL. Thus, a small
dot is formed on the recording paper 8. Correspondingly to the
middle-dot dot-pattern data, a middle-dot drop of the ink is jetted
from the nozzle 13. The volume of the jetted middle-dot drop of the
ink is 9 to 15 pL. Thus, a middle dot is formed on the recording
paper 8. Correspondingly to the large-dot dot-pattern data, two
drops of the ink are jetted from the nozzle 13. The volume of the
jetted two drops of the ink is 17 to 30 pL in total. Thus, a large
dot is formed on the recording paper 8.
As described above, in the second mode, the pulse-selecting data
consists of the two bits. Thus, the driving pulse can be generated
at an extremely high speed. Thus, recording by the second mode can
be conducted at a high speed. In addition, since the middle dot is
formed by one drop of the ink and the large dot is formed by a
combination of the two drops of the ink, quality of a recorded
image is superior to the first mode. However, since only the volume
of 30 pL of the ink is jetted for a large dot in one path,
recording speed by the second mode is inferior to the first mode.
In addition, since the large dot is formed by the combination of
the two drops of the ink, quality of the recorded image is inferior
to the third mode.
Next, the case wherein the driving signal C shown in FIGS. 9 and 10
is used (the third quality mode) is explained.
In the case, the decoder 42 generates pulse-selecting data
consisting of ten bits, based on the small-dot dot-pattern data
(level data 01), the middle-dot dot-pattern data (level data 10)
and the large-dot dot-pattern data (level data 11),
respectively.
Each of the ten bits corresponds to each of the pulse-waves and the
connecting elements. That is, an uppermost bit of the
pulse-selecting data corresponds to the first pulse-wave PS11 in
the part T1 of the period TB. A second uppermost bit of the
pulse-selecting data corresponds to the second pulse-wave PS12 in
the part T2 of the period TB. A third uppermost bit of the
pulse-selecting data corresponds to the first connecting element
CP1 in the part TS1 of the period TB. A fourth uppermost bit of the
pulse-selecting data corresponds to the third pulse-wave PS13 in
the part T3 of the period TB. A fifth uppermost bit of the
pulse-selecting data corresponds to the fourth pulse-wave PS14 in
the part T4 of the period TB. A sixth uppermost bit of the
pulse-selecting data corresponds to the fifth pulse-wave PS15 in
the part T5 of the period TB. A seventh uppermost bit of the
pulse-selecting data corresponds to the second connecting element
CP2 in the part TS2 of the period TB. An eighth uppermost bit of
the pulse-selecting data corresponds to the sixth pulse-wave PS16
in the part T6 of the period TB. A ninth uppermost bit of the
pulse-selecting data corresponds to the third connecting element
CP3 in the part TS3 of the period TB. A lowermost (tenth uppermost)
bit of the pulse-selecting data corresponds to the seventh
pulse-wave PS17 in the part T7 of the period TB.
The bits corresponding to the connecting elements are always set
"0".
In the case, the pulse-selecting data generated based on the
small-dot dot-pattern data (level data 01) is "0100000100".
Similarly, the pulse-selecting data generated based on the
middle-dot dot-pattern data (level data 10) is "0001000000", and
the pulse-selecting data generated based on the large-dot
dot-pattern data (level data 11) is "0000100001".
When the uppermost bit of the pulse-selecting data is "1", the
switching circuit 45 (driving-pulse generator) is closed
(connected) from a first timing signal (LAT signal), which is
generated when the part T1 of the period TB starts, to a second
timing signal (CH signal), which is generated when the part T2 of
the period TB starts. Thus, the first pulse-wave PS11 is picked out
from the driving signal C and supplied to the corresponding
piezoelectric vibrating member 15. Similarly, when the second
uppermost bit of the pulse-selecting data is "1", the switching
circuit 45 is closed from the second timing signal to a third
timing signal (CH signal), which is generated when the part TS1 of
the period TB starts. Thus, the second pulse-wave PS12 is picked
out from the driving signal C and supplied to the corresponding
piezoelectric vibrating member 15. In the same way, when another
bit (of the third bit to the tenth bit) of the pulse-selecting data
is "1", the corresponding pulse-wave is picked out from the driving
signal C and supplied to the corresponding piezoelectric vibrating
member 15.
Thus, based on the small-dot dot-pattern data, the second
pulse-wave PS12 and the sixth pulse-wave PS16 are supplied to the
corresponding piezoelectric vibrating member 15. In addition, based
on the middle-dot dot-pattern data, only the third pulse-wave PS13
is supplied to the corresponding piezoelectric vibrating member 15.
Similarly, based on the large-dot dot-pattern data, the fourth
pulse-wave PS14 and the seventh pulse-wave PS17 are supplied to the
corresponding piezoelectric vibrating member 15.
As a result, correspondingly to the small-dot dot-pattern data, the
small-dot driving pulse DP3 is supplied to the corresponding
piezoelectric vibrating member 15. Then, a small-dot drop of the
ink is jetted from the nozzle 13. The volume of the jetted
small-dot drop of the ink is 0.5 to 4 pL. Thus, a small dot is
formed on the recording paper 8. Correspondingly to the middle-dot
dot-pattern data, the middle-dot driving pulse DP4 is supplied to
the corresponding piezoelectric vibrating member 15. Then, a
middle-dot drop of the ink is jetted from the nozzle 13. The volume
of the jetted middle-dot drop of the ink is 5 to 10 pL. Thus, a
middle dot is formed on the recording paper 8. Correspondingly to
the large-dot dot-pattern data, the large-dot driving pulse DP5 is
supplied to the corresponding piezoelectric vibrating member 15.
Then, a large-dot drop of the ink is jetted from the nozzle 13. The
volume of the jetted large-dot drop of the ink is 10 to 20 pL.
Thus, a large dot is formed on the recording paper 8.
As described above, in the third mode, since the large dot as well
as the middle dot is formed by one drop of the ink, quality of a
recorded image is extremely high. However, since the
pulse-selecting data consists of the ten bits, it needs a
relatively long time to generate the driving pulse. In addition,
since only the volume of 20 pL of the ink is jetted for a large dot
in one path, recording speed by the third mode is inferior to the
first mode and the second mode.
Operation of the Printer
Then, an operation of the printer 1 is explained.
Before starting a recording operation, a selected quality mode is
set from the plurality of quality modes (the first mode, the second
mode and the third mode) via the interface unit 100. The selected
quality mode may be automatically set in the main controller 28
according to a controlling command transmitted from the host
computer or the like, instead of via the interface unit 100.
After the selected quality mode is set, the main controller 28
outputs control information (quality mode information) to the
driving-signal generator 30 and the decoder 42.
The driving-signal generator 30 is ready to generate a driving
signal corresponding to the selected quality mode, based on the
control information. For example, when the driving-signal generator
30 receives control information that the selected quality mode is
the first quality mode, the driving-signal generator 30 is ready to
generate the driving signal A shown in FIG. 5. Similarly, when the
driving-signal generator 30 receives control information that the
selected quality mode is the second quality mode, the
driving-signal generator 30 is ready to generate the driving signal
B shown in FIG. 7. Similarly, when the driving-signal generator 30
receives control information that the selected quality mode is the
first quality mode, the driving-signal generator 30 is ready to
generate the driving signal C shown in FIG. 9.
The decoder 42 sets a relationship between the printing data (level
data) and the pulse-selecting data. For example, the decoder 42
selects a table data, which defines a relationship between the
printing data and the pulse-selecting data, for the selected
quality mode from a plurality of table data for the respective
quality modes, based on the control information from the main
controller 28.
Then, the printer 1 conducts a recording operation based on the
selected quality mode.
That is, in the first mode, the driving-signal generating circuit
30 generates the driving signal A including the series of the first
driving pulse DP6, the second driving pulse DP7 and the third
driving pulse DP8. The decoder 42 generates the pulse-selecting
data "010" by translating the small-dot printing data (level data
01). Similarly, the decoder 42 generates the pulse-selecting data
"101" by translating the middle-dot printing data (level data 10).
Similarly, the decoder 42 generates a pulse-selecting data "111" by
translating the large-dot printing data (level data 11).
The switching circuit 45 confirms corresponding one of the bits
forming the pulse-selecting data, whenever a timing signal is
inputted from the controlling logic circuit 43, that is, every
timing defined by the latch signals (LAT) and the channel signals
(CH). When a bit of the pulse-selecting data is "1", the
corresponding pulse-wave (a part of the driving signal for the
corresponding time) is supplied to the piezoelectric vibrating
member 15.
As a result, based on the small-dot printing data, only the second
driving pulse DP7 is supplied to the corresponding piezoelectric
vibrating member 15. Then, one small-dot drop of the ink, which has
a volume of 13 pL, is jetted from the nozzle 13. In addition, based
on the middle-dot printing data, only the first driving pulse DP6
and the third driving pulse DP8 are supplied to the corresponding
piezoelectric vibrating member 15 in turn. Then, two small-dot
drops of the ink, each of which has a volume of 13 pL, are jetted
from the nozzle 13. Similarly, based on the large-dot printing
data, all the first driving pulse DP6, the second driving pulse DP7
and the third driving pulse DP8 are supplied to the corresponding
piezoelectric vibrating member 15 in succession. Then, three
small-dot drops of the ink, each of which has a volume of 13 pL,
are jetted from the nozzle 13.
Alternatively, in the second mode, the driving-signal generating
circuit 30 generates the driving signal B including the series of
the small-dot driving pulse DP1 for jetting a small-dot drop of the
ink and the middle-dot driving pulse DP2 for jetting a middle-dot
drop of the ink. The decoder 42 generates the pulse-selecting data
"10" by translating the small-dot printing data (level data 01).
Similarly, the decoder 42 generates the pulse-selecting data "01"
by translating the middle-dot printing data (level data 10).
Similarly, the decoder 42 generates a pulse-selecting data "11" by
translating the large-dot printing data (level data 11).
The switching circuit 45 confirms corresponding one of the bits
forming the pulse-selecting data, whenever a timing signal is
inputted from the controlling logic circuit 43. When a bit of the
pulse-selecting data is "1", the corresponding pulse-wave (a part
of the driving signal for the corresponding time) is supplied to
the piezoelectric vibrating member 15.
As a result, based on the small-dot printing data, only the
small-dot driving pulse DP1 is supplied to the corresponding
piezoelectric vibrating member 15. Then, a small-dot drop of the
ink, which has a volume of 3 to 9 pL, is jetted from the nozzle 13.
In addition, based on the middle-dot printing data, only the
middle-dot driving pulse DP2 is supplied to the corresponding
piezoelectric vibrating member 15. Then, a middle-dot drop of the
ink, which has a volume of 9 to 15 pL, is jetted from the nozzle
13. Similarly, based on the large-dot printing data, the small-dot
driving pulse DP1 and the middle-dot driving pulse DP2 are supplied
to the corresponding piezoelectric vibrating member 15 in
succession. Then, a small-dot drop of the ink and a middle-dot drop
of the ink, which are combined into a total volume of 17 to 30 pL,
are jetted from the nozzle 13.
Alternatively, in the third mode, the driving-signal generating
circuit 30 generates the driving signal C including the small-dot
driving pulse DP3 for jetting a small-dot drop of the ink, the
middle-dot driving pulse DP4 for jetting a middle-dot drop of the
ink, and the large-dot driving pulse DP5 for jetting a large-dot
drop of the ink. The decoder 42 generates the pulse-selecting data
"0100000100" by translating the small-dot printing data (level data
01). Similarly, the decoder 42 generates the pulse-selecting data
"0001000000" by translating the middle-dot printing data (level
data 10). Similarly, the decoder 42 generates a pulse-selecting
data "0000100001" by translating the large-dot printing data (level
data 11).
The switching circuit 45 confirms corresponding one of the bits
forming the pulse-selecting data, whenever a timing signal is
inputted from the controlling logic circuit 43. When a bit of the
pulse-selecting data is "1", the corresponding pulse-wave (a part
of the driving signal for the corresponding time) is supplied to
the piezoelectric vibrating member 15.
As a result, based on the small-dot printing data, only the
small-dot driving pulse DP3 is supplied to the corresponding
piezoelectric vibrating member 15. Then, a small-dot drop of the
ink, which has a volume of 0.5 to 4 pL, is jetted from the nozzle
13. In addition, based on the middle-dot printing data, only the
middle-dot driving pulse DP4 is supplied to the corresponding
piezoelectric vibrating member 15. Then, a middle-dot drop of the
ink, which has a volume of 5 to 10 pL, is jetted from the nozzle
13. Similarly, based on the large-dot printing data, the large-dot
driving pulse DP5 is supplied to the corresponding piezoelectric
vibrating member 15. Then, a large-dot drop of the ink, which has a
volume of 10 to 20 pL, is jetted from the nozzle 13.
As described above, according to the embodiment, a relationship
(combinations) of the respective printing data (level data) and the
volumes of the jetted ink based on a quality mode is different from
another relationship based on another quality mode.
Thus, with respect to the same printing data, volumes of the ink
jetted from the nozzle based on the respective selected quality
modes are different. For example, with respect to the small-dot
printing data (level data 01), the volume of the ink jetted by the
first mode is 13 pL, the volume of the ink jetted by the second
mode is 3 to 9 pL, and the volume of the ink jetted by the third
mode is 0.5 to 4 pL. With respect to the middle-dot printing data
(level data 10), the volume of the ink jetted by the first mode is
26 (13.times.2) pL, the volume of the ink jetted by the second mode
is 9 to 15 pL, and the volume of the ink jetted by the third mode
is 5 to 10 pL. With respect to the large-dot printing data (level
data 11), the volume of the ink jetted by the first mode is 39
(13.times.3) pL, the volume of the ink jetted by the second mode is
17 to 30 pL, and the volume of the ink jetted by the third mode is
10 to 20 pL.
Thus, the respective volumes of the ink corresponding to the
respective level data of the printing data can be set more
diversely, which can satisfy user's various demands. For example,
by using the first mode, a text including characters or the like
can be recorded at a very high speed. By using the second mode, an
image can be recorded with a high quality while keeping a
relatively high speed. In addition, by using the third mode, an
image can be recorded with a extremely high quality. FIG. 12 shows
the relationship between the volumes of the ink jetted by the
respective quality modes and qualities of recorded images by the
respective quality modes in the embodiment.
Another Driving Signal
The driving signals defined in the respective quality modes are not
limited by the above description. As one modified example, a
driving signal D is explained with reference to FIGS. 12 and 13.
The driving signal D can be generated in a second mode.
As shown in FIG. 12, the driving signal D is a periodical signal
having a recording period TD. The recording period TD is divided
into a part T1 including a first pulse-wave PS31, a part TS1
including a first connecting element CP31, a part T2 including a
second pulse-wave PS32, a part TS2 including a second connecting
element CP32, a part T3 including a third pulse-wave PS33, and a
part T4 including a fourth pulse-wave PS34. The first pulse-wave
PS31, the first connecting element CP31, the second pulse-wave
PS32, the second connecting element CP32, the third pulse-wave
PS33, and the fourth pulse-wave PS34 are connected in a series
manner.
Each of the connecting elements CP31 and CP32 is an element
connecting an electric-potential level of the previous pulse-wave
and an electric-potential level of the next pulse-wave. The
connecting elements CP31 and CP32 are not supplied to the
piezoelectric vibrating member 15.
In the case, the sum of a length of the part T1 and a length of the
part TS1 is equal to the sum of a length of the part TS2 and a
length of the part T3.
As shown in FIG. 13, in the driving signal D, the first pulse-wave
PS31 is adapted to function as a part of a small-dot driving pulse
DP11 for jetting a small-dot drop of the ink from the nozzle 13.
The second pulse-wave PS32 is adapted to function as an additional
large-dot driving pulse DP12 for jetting an additional (second)
drop of the ink from the nozzle 13. The additional drop of the ink
may be combined with a middle-dot drop of the ink (described below)
to correspond to a large-dot drop of the ink. The third pulse-wave
PS33 is adapted to function as a part of the small-dot driving
pulse DP11 to form the small-dot driving pulse DP11 together with
the first pulse-wave PS31. The fourth pulse-wave PS34 is adapted to
function as a middle-dot driving pulse DP13 for jetting a
middle-dot drop of the ink from the nozzle 13.
That is, as shown in FIG. 13, when the first pulse-wave PS31 and
the third pulse-wave PS33 are picked out from the driving signal D,
the small-dot driving pulse DP11 (a third small-dot driving pulse)
is generated. Similarly, when the fourth pulse-wave PS34 is picked
out from the driving signal D, the middle-dot driving pulse DP13 (a
third middle-dot driving pulse) is generated. Similarly, when the
second pulse-wave PS32 and the fourth pulse-wave PS34 are picked
out from the driving signal D, a combination of the additional
large-dot driving pulse DP12 and the middle-dot driving pulse DP13
is generated as a large-dot driving pulse.
As shown in FIGS. 12 and 13, the small-dot driving pulse DP11
includes: a first charging element P71 rising from a middle
electric potential VM to a third highest electric potential VH3 at
a relatively gentle incline .theta.51, a first holding element P72
maintaining the third highest electric potential VH3 for a
relatively long time, a first discharging element P73 falling from
the third highest electric potential VH3 to a lowest electric
potential VL at a steep incline .theta.52, a second holding element
P74 maintaining the lowest electric potential VL for a
predetermined time, a second charging element P75 rising from the
lowest electric potential VL to a highest electric potential VH at
a steep incline .theta.53, a third holding element P76 maintaining
the highest electric potential VH for a very short time, a second
discharging element P77 falling from the highest electric potential
VH to a second middle electric potential VM2 at a steep incline
.theta.54, a fourth holding element P78 maintaining the second
middle electric potential VM2 for a very short time, a third
charging element P79 rising from the second middle electric
potential VM2 to a second highest electric potential VH2 at a steep
incline .theta.55, a fifth holding element P80 maintaining the
second highest electric potential VH2 for a short time, and a third
discharging element P81 falling back from the second highest
electric potential VH2 to the middle electric potential VM at a
incline .theta.56.
The second highest electric potential VH2 is set slightly lower
than the highest electric potential VH. The third highest electric
potential VH3 is set between the middle electric potential VM and
the second highest electric potential VH2. The second middle
electric potential VM2 is set between the middle electric potential
VM and the lowest electric potential VL.
When the small-dot driving pulse DP11 is supplied to the
piezoelectric vibrating member 15, a small-dot drop of the ink,
whose volume corresponds to a small dot, is jetted from the nozzle
13.
In detail, when the first charging element P71 is supplied to the
piezoelectric vibrating member 15, the piezoelectric vibrating
member 15 is charged from the middle electric potential VM. Then,
the corresponding pressure chamber 16 is caused to gradually
contract from a standard volume thereof (corresponding to the
middle electric potential VM) to a smaller volume thereof
(corresponding to the third highest electric potential VH3). The
pressure chamber 16 maintains the smaller volume thereof while the
first holding element P72 is supplied to the piezoelectric
vibrating member 15. Then, the pressure chamber 16 is caused to
rapidly expand by the first discharging element P73, to contract
again by the second charging element P75, and to expand again by
the second discharging element P77. Such a series of contractions
and expansions of the pressure chamber 16 causes a pressure of the
ink in the pressure chamber 16 to change so that a small-dot drop
of the ink is jetted from the nozzle 13. A volume of the jetted
drop of the ink is as little as 0.5 to 4 pL. Then, the third
charging element P79, the fifth holding element P80 and the third
discharging element P81 are supplied to the piezoelectric vibrating
member 15 in turn. Thus, the pressure chamber 16 is caused to
contract and expand back in order to settle down a vibration of a
meniscus of the ink at the nozzle 13 within a short time after the
drop of the ink is jetted.
The middle-dot driving pulse DP13 includes: a fourth discharging
element P82 falling from the middle electric potential VM to a
second lowest electric potential VL2 at a incline .theta.57, the
second lowest electric potential VL2 being set between the second
middle electric potential VM2 and the lowest electric potential VL,
a sixth holding element P83 maintaining the second lowest electric
potential VL2 for a time, a fourth charging element P84 rising from
the second lowest electric potential VL2 to the highest electric
potential VH at a steep incline .theta.58, a seventh holding
element P85 maintaining the highest electric potential VH for a
predetermined time, and a fifth discharging element P86 falling
back from the highest electric potential VH to the middle electric
potential VM at a steep incline .theta.59.
When the middle-dot driving pulse DP13 is supplied to the
piezoelectric vibrating member 15, a middle-dot drop of the ink,
whose volume corresponds to a middle dot, is jetted from the nozzle
13.
In detail, when the fourth discharging element P82 is supplied to
the piezoelectric vibrating member 15, the piezoelectric vibrating
member 15 is discharged from the middle electric potential VM.
Then, the corresponding pressure chamber 16 is caused to gradually
expand from the standard volume thereof to a larger volume thereof
corresponding to the second lowest electric potential VL2. The
pressure chamber 16 maintains the larger volume thereof for a time,
that is, while the sixth holding element P83 is supplied to the
piezoelectric vibrating member 15. Then, the pressure chamber 16 is
caused to rapidly contract to the minimum volume thereof
corresponding to the highest electric potential VH by the fourth
charging element P84. Such a contraction of the pressure chamber 16
raises a pressure of the ink in the pressure chamber 16 so that a
middle-dot drop of the ink is jetted from the nozzle 13. The
pressure chamber 16 maintains such a minimum contracting state
thereof for a predetermined time, that is, while the seventh
holding element P85 is supplied to the piezoelectric vibrating
member 15. Thus, a volume of the jetted middle-dot drop of the ink
is as much as 9 to 15 pL. Then, the fifth discharging element P86
is supplied to the piezoelectric vibrating member 15. Thus, the
pressure chamber 16 is caused to expand back to the standard volume
thereof in order to settle down a vibration of a meniscus of the
ink at the nozzle 13 within a short time after the drop of the ink
is jetted.
In the case, the additional large-dot driving pulse DP12 has the
same waveform as the middle-dot driving pulse DP13. That is, the
additional large-dot driving pulse DP12 includes: a sixth
discharging element P87 falling from the middle electric potential
VM to the second lowest electric potential VL2 at the incline
.theta.57, an eighth holding element P88 maintaining the second
lowest electric potential VL2 for the time, a fifth charging
element P89 rising from the second lowest electric potential VL2 to
the highest electric potential VH at the steep incline .theta.58, a
ninth holding element P90 maintaining the highest electric
potential VH for the predetermined time, and a seventh discharging
element P91 falling back from the highest electric potential VH to
the middle electric potential VM at the steep incline
.theta.59.
When both the additional large-dot driving pulse DP12 and the
middle-dot driving pulse DP13 are supplied to the piezoelectric
vibrating member 15 in succession, an additional drop of the ink
and a middle-dot drop of the ink are jetted for a large-dot.
Next, in the case, pulse-selecting data generated based on the
small-dot dot-pattern data (level data 01), the middle-dot
dot-pattern data (level data 10) and the large-dot dot-pattern data
(level data 11) are explained in detail.
In the case, the decoder 42 generates pulse-selecting data
consisting of six bits, based on the small-dot dot-pattern data
(level data 01), the middle-dot dot-pattern data (level data 10)
and the large-dot dot-pattern data (level data 11),
respectively.
Each of the six bits corresponds to each of the pulse-waves and the
connecting elements. That is, an uppermost bit of the
pulse-selecting data corresponds to the first pulse-wave PS31 in
the part T1 of the period TD. A second uppermost bit of the
pulse-selecting data corresponds to the first connecting element
CP31 in the part TS1 of the period TD. A third uppermost bit of the
pulse-selecting data corresponds to the second pulse-wave PS32 in
the part T2 of the period TD. A fourth uppermost bit of the
pulse-selecting data corresponds to the second connecting element
CP32 in the part TS2 of the period TD. A fifth uppermost bit of the
pulse-selecting data corresponds to the third pulse-wave PS33 in
the part T3 of the period TD. A sixth uppermost bit of the
pulse-selecting data corresponds to the fourth pulse-wave PS34 in
the part T4 of the period TD.
The bits corresponding to the connecting elements are always set
"0".
In the case, the pulse-selecting data generated based on the
small-dot dot-pattern data (level data 01) is "100010". Similarly,
the pulse-selecting data generated based on the middle-dot
dot-pattern data (level data 10) is "000001", and the
pulse-selecting data generated based on the large-dot dot-pattern
data (level data 11) is "001001".
When the uppermost bit of the pulse-selecting data is "1", the
switching circuit 45 (driving-pulse generator) is closed
(connected) from a first timing signal (LAT signal), which is
generated when the part T1 of the period TD starts, to a second
timing signal (CH signal), which is generated when the part T2 of
the period TD starts. Thus, the first pulse-wave PS31 is picked out
from the driving signal D and supplied to the corresponding
piezoelectric vibrating member 15. Similarly, when the third
uppermost bit of the pulse-selecting data is "1", the switching
circuit 45 is closed from a third timing signal (CH signal), which
is generated when the part T2 of the period TD starts, to a fourth
timing signal (CH signal), which is generated when the part TS2 of
the period TD starts. Thus, the second pulse-wave PS32 is picked
out from the driving signal D and supplied to the corresponding
piezoelectric vibrating member 15. In the same way, when the fifth
bit or the sixth bit of the pulse-selecting data is "1", the
corresponding pulse-wave is picked out from the driving signal D
and supplied to the corresponding piezoelectric vibrating member
15.
Thus, based on the small-dot dot-pattern data, the first pulse-wave
PS31 and the third pulse-wave PS33 are supplied to the
corresponding piezoelectric vibrating member 15. In addition, based
on the middle-dot dot-pattern data, only the fourth pulse-wave PS34
is supplied to the corresponding piezoelectric vibrating member 15.
Similarly, based on the large-dot dot-pattern data, the second
pulse-wave PS32 and the fourth pulse-wave PS34 are supplied to the
corresponding piezoelectric vibrating member 15.
As a result, correspondingly to the small-dot dot-pattern data, the
small-dot driving pulse DP11 is supplied to the corresponding
piezoelectric vibrating member 15. Then, a small-dot drop of the
ink is jetted from the nozzle 13. The volume of the jetted
small-dot drop of the ink is 3 to 9 pL. Thus, a small dot is formed
on the recording paper 8. Correspondingly to the middle-dot
dot-pattern data, the middle-dot driving pulse DP13 is supplied to
the corresponding piezoelectric vibrating ember 15. Then, a
middle-dot drop of the ink is jetted from the nozzle 13. The volume
of the jetted middle-dot drop of the ink is 9 to 15 pL. Thus, a
middle dot is formed on the recording paper 8. Correspondingly to
the large-dot dot-pattern data, the additional large-dot driving
pulse DP12 and the middle-dot driving pulse DP13 are supplied to
the corresponding piezoelectric vibrating member 15 in succession.
Then, two drops of the ink are jetted from the nozzle 13. The
volume of the jetted two drops of the ink is 17 to 30 pL in total.
Thus, a large dot is formed on the recording paper 8.
As described above, in the second mode using the driving signal D,
the pulse-selecting data consists of the six bits. Thus, the
driving pulse can be generated faster than the third mode. In
addition, since the middle dot is formed by one drop of the ink and
the large dot is formed by a combination of the two drops of the
ink, quality of a recorded image is superior to the first mode.
However, since only the volume of 30 pL of the ink is jetted for a
large dot in one path, recording speed by the second mode is
inferior to the first mode. In addition, since the large dot is
formed by the combination of the two drops of the ink, quality of
the recorded image is inferior to the third mode.
In addition, other advantages in the second mode using the driving
signal D are explained.
In the case, since the sum of the length of the part T1 and the
length of the part TS1 is equal to the sum of the length of the
part TS2 and the length of the part T3, the two drops of the ink
for a large dot can be jetted in an identical cycle. In addition,
since the additional large-dot driving pulse DP12 and the
middle-dot driving pulse DP13 have the same wave form, each of the
two drops of the ink for a large dot can have the same volume.
Thus, when the recording operation is conducted in a two-way
(reciprocative) manner of forth and back, the same recording
condition can be achieved whether the recording head 10 may move
forth or back.
In addition, since a main part of the small-dot driving pulse DP11
is arranged between the additional large-dot driving pulse DP12 and
the middle-dot driving pulse DP13, a point to which the small-dot
drop of the ink is jetted can be substantially the same as a point
to which the two drops of the ink for a large dot are jetted. This
can lead to improve the quality of the recorded image.
A pressure-changing unit for causing the volume of the pressure
chamber 16 to change is not limited to the piezoelectric vibrating
member 15. For example, a pressure-changing unit can consist of a
magnetostrictive device. In the case, the magnetic distortion
device causes the pressure chamber 16 to expand and contract, thus,
causes the pressure of the ink in the pressure chamber 16 to
change. Alternatively, a pressure-changing unit can consist of a
heating device. In the case, the heating device causes an air
bubble in the pressure chamber 16 to expand and contract, thus,
causes the pressure of the ink in the pressure chamber 16 to
change.
As described above, the printer controller 1 can be materialized by
a computer system. A program for materializing the above one or
more components in a computer system, and a storage unit 201
storing the program and capable of being read by a computer, are
intended to be protected by this application. In addition, when the
above one or more components may be materialized in a computer
system by using a general program such as an OS, a program
including a command or commands for controlling the general
program, and a storage unit 202 storing the program and capable of
being read by a computer, are intended to be protected by this
application.
Each of the storage units 201 and 202 can be not only a substantial
object such as a floppy disk or the like, but also a network for
transmitting various signals.
The above description is given for the ink-jetting printer 1 as a
liquid jetting apparatus of a first embodiment according to the
invention. However, this invention is intended to apply to general
liquid jetting apparatuses widely. A liquid may be glue, nail
polish or the like, instead of the ink.
As described above, according to the invention, the driving signal
is generated based on the selected jetting mode, and the driving
pulse is generated based on the driving signal and the selected
level data based on the jetting data. Thus, a manner of jetting the
liquid by the driving pulse may be controlled by two factors of the
jetting mode and the level data, which may enable to satisfy the
user's various demands.
* * * * *